Changelog for VirtualBox 4.0

This page lists all changes of the VirtualBox 4.0 releases.
All branches: 7.1 · 7.0 · 6.1 · 6.0 · 5.2 · 5.1 · 5.0 · 4.3 · 4.2 · 4.1 · 4.0

VirtualBox 4.0.x is no longer supported!

VirtualBox 4.0.36 (released 2015-11-11)

This is a maintenance release. The following items were fixed and/or added:

• several fixes

VirtualBox 4.0.34 (released 2015-10-20)

This is a maintenance release. The following items were fixed and/or added:

• several fixes
• Windows hosts: hardening fixes

VirtualBox 4.0.32 (released 2015-07-10)

This is a maintenance release. The following items were fixed and/or added:

• Linux hosts: fixed a bug which made the netfilter driver ignore certain events (bug #12264)

VirtualBox 4.0.30 (released 2015-05-19)

This is a maintenance release. The following items were fixed and/or added:

• VRDP: fixed incompatibility with rdesktop 1.8.3
• Floppy: several fixes

VirtualBox 4.0.28 (released 2015-01-17)

This is a maintenance release. The following items were fixed and/or added:

• VRDP: fixed a rare crash when using remote audio input
• Storage: fixed data corruption when resizing VHD images under certain circumstances

VirtualBox 4.0.26 (released 2014-07-15)

This is a maintenance release. The following items were fixed and/or added:

• HGCM: fixed a problem with saved states which could cause several guest misbehavior after a VM was started from a saved state

VirtualBox 4.0.24 (released 2014-03-14)

This is a maintenance release. The following items were fixed and/or added:

• 3D: several fixes
• Additions: fixed CPU hot-remove on newer Linux kernels

VirtualBox 4.0.22 (released 2014-01-10)

This is a maintenance release. The following items were fixed and/or added:

• HGCM: fixed crashes under certain conditions
• Linux Additions: fixes for recent Linux kernels
• Windows Additions: fixed guest crashes in in Shared Folders service under certain conditions

VirtualBox 4.0.20 (released 2013-10-11)

This is a maintenance release. The following items were fixed and/or added:

• GUI: prevent crashes under certain conditions on X11 hosts
• VRDP: fixed a rare crash on the guest screen resize
• Storage: fixed data corruption after resizing a VDI image under certain circumstances (bug #11344)
• Storage: fixed crash when connecting to certain QNAP iSCSI targets
• Storage: fixed lost writes if iSCSI is used with snapshots and ansyc I/O (bug #11479)
• Storage: fixed hang when creating a snapshot using Parallels disk images (bug #9617)
• VBoxSVC: don't crash on systems with many VLAN interfaces
• Main/OVF: don't crash during import if the client forgot to call Appliance::interpret() (bug #10845)
• VBoxManage: don't crash during screenshotpng if there is no display (bug #11363)
• Linux hosts: work around gcc bug 55940 which might lead to wrong kernel module code if gcc 4.7 is used to compile the 32-bit Linux host kernel (bug #11035)
• Linux hosts: made "]" key work again on Japanese keyboards.
• Linux hosts / guests: Linux 3.11 fixes (bug #11946, #12001)
• Solaris / Mac OS X hosts: VM CPU load metrics now report 100% when all cores are fully utilized (used to be a single core)
• Linux Additions: Linux 3.8 / 3.9 compile fixes (bug #11036)
• Linux Additions: RHEL/OEL/CentOS 6.4 compile fix (bug #11586)
• Linux Additions: Debian Linux kernel 3.2.0-4 (3.2.39) compile fix (bug #11634)

VirtualBox 4.0.18 (released 2012-12-18)

This is a maintenance release. The following items were fixed and/or added:

• VMM: fixed VERR_NOT_SUPPORTED and VERR_RAW_MODE_INVALID_SMP guru meditation due to an invalid reschedule to raw mode (bug #10370)
• VMM: fixed a potential problem causing to schedule interrupts during SYSEXIT right after STI
• VMM: fixed a VM hang after a resume from pause / savestate with SMP guests in rare cases
• VMM: fixed a potential guest memory corruption issue in page fusion
• VMM: fixed host freezes with 64-bit guests on 32-bit Linux hosts (bug #10528)
• VMM: fixed an interpretion bug for TPR read instructions under rare conditions (AMD-V only)
• VMM: fixed handling of task gates if VT-x/AMD-V is disabled
• Snapshots: fixed a crash when restoring an old snapshot when powering off a VM (bug #10491)
• Main: host interfaces no longer have "defaults" for ip address and network mask attributes
• Network: fixed the problem with packets larger than MTU-4 when PCnet or PRO/1000 was bridged to certain types of adapters on OS X host (bug #3783)
• Bridged Networking: fixed the problem with device driver unloading on kernels 3.2.18 and newer due to invalid reference counter (bug #10624)
• NAT: fixed a crash under rare circumstances (Windows hosts only; bug #10128)
• Virtio-net: fixed the problem with receiving of GSO packets in Windows XP guests causing packet loss in host-to-VM transfers
• Virtio-net: fixed the problem with network statistics counters in Session Information dialog (GUI)
• Storage: fixed a possible data corruption when compacting VDI images with snapshots
• Storage: fixed audio CD passthrough for certain media players
• Storage: fixed hang in case of unaligned requests and async I/O enabled
• Storage: fixed hang with newer VHD images (bug #11279)
• VGA: fixed wrong access check which might cause a crash under certain conditions
• VGA: fix for double scan text modes
• USB: don't crash if a USB device is plugged or unplugged when saving or loading the VM state (SMP guests only)
• VBoxManage: fixed memory leak when executing and waiting for a guest process
• VBoxManage: fixed converting disks from raw images
• Solaris installer: fixed dependency checking while installing VirtualBox in a zone
• Linux hosts / guests: fixes for Linux 3.3, 3.4, 3.5 and 3.7
• Linux Additions: make 3D passthrough work on OEL/RHEL 6.2 (bug #10010)
• Linux Additions: fixed missing implementation when copying shared folder data through kernel high memory (bug #9878)
• Linux Additions: make sure all data is written when closing a memory mapped file on a shared folder
• Linux Additions: the guest content was sometimes not properly updated (bug #9887)
• Solaris Additions: fixed guest kernel driver to load properly on guest reboot (4.1.8 regression; bug #10113)
• Solaris Additions: fixed missing 64-bit OpenGL library VBoxOGL.so (bug #10151)
• Windows Additions, VRDP: fixed occasional corruption of vertical text

VirtualBox 4.0.16 (released 2012-01-11)

This is a maintenance release. The following items were fixed and/or added:

• VRDP: fixed screen corruption
• VRDP: fixed screen freeze
• ATA: fixed a possible crash during ATAPI passthrough with certain guests
• NAT: the interface stopped working after a lot of failed ICMP requests (bug #9371)
• Metrics: fixed potential problem with invalid access in guest metrics collection upon VM destruction
• Main: fixed incorrect framebuffer information after leaving the fullscreen mode with X11 guests, this lead to a scrambled preview window in the GUI for example
• VBoxSVC: fixed crash under rare circumstances (e.g. client crash)
• VMDK/VHD: fixed a possible corruption with host cache disabled when using snapshots under rare circumstances (bug #9749)
• OVF/OVA: fixed broken disk images on import under rare circumstances
• Mac OS X hosts: fixed the problem with duplicate packets when bridged to wireless interface (bug #9648)
• Windows Additions: implemented faster detection of logged-in guest users and stale sessions
• Linux guests: fixes for Linux 3.2

VirtualBox 4.0.14 (released 2011-10-18)

This is a maintenance release. The following items were fixed and/or added:

• VMM: fixed 64bit guests on AMD Fusion CPUs (bug #8824)
• VMM: fixed handling of the sysenter/sysexit machine instructions in 64-bit guests on Intel hosts
• GUI: fixed the inclusion of additional information (license, vendor, ...) on OVF export
• GUI: when taking a snapshot from the VM selector, don't do a live snapshot
• GUI: fixed spurious LCtrl key events on some Windows hosts (4.0.6 regression; bug #373)
• VBoxManage: fixed extpack install --replace
• VRDP: fixed a rare screen corruption
• E1000: fixed rare Windows 7 guest hangs, either at boot time or when reconfiguring the network card in unusual setups (bug #6223)
• Mouse support: fixed an off-by-one pointer position error affecting Windows guests (bugs #7566, #9321)
• NAT: changed TCP connection establishment according to Winsock API requirements (Windows hosts only; bug #8919)
• VHD: fixed reads crossing block boundaries (bug #8532)
• VMDK: fixed progress indicator when creating split VMDK images
• Floppy: fixed medium size detection for physical mediums (Windows hosts only)
• VBoxSVC: made the path comparison OS independent when images are registered (bug #9303)
• Main: return the correct RDP default port fixing settings warnings in the GUI if the remote display was enabled at runtime (bug #9368)
• Main: fix VM initialization if a shared folder does not exist (bug #7941)
• Main: fixed taking screen shots (e.g. the preview window) for headless VMs if the Guest Additions are active
• Main: fixed possible deadlock between hard disk enumeration and the resetting of immutable disks (bug #9549)
• OVA: fixed import of renamed OVA files (bug #9033)
• Virtio-net: fixed the problem with UDP packets exceeding MTU (bug #9370)
• Solaris hosts: fixed starting EFI guests due to missing EFI ROM files (bug #9535)
• Mac OS X hosts: fix installation issues when installed as root (bug #1578)
• Windows Additions: fixed file truncation on a shared folder with some applications (bugs #9276, #9315)
• Linux Additions: suppress an incorrect error message and allow a shared folder to be mounted in multiple places (bug #9627)
• Linux Additions: add support for X.Org Server 1.11 (bug #9519)
• Linux Additions: fixed llseek for Linux kernels 2.6.37 and above
• Linux Additions: start VBoxService correctly on openSUSE 12.1 (bug #6229)
• Linux Additions: properly finish the installation even if the compilation of the DRM module fails (which is not fatal)

VirtualBox 4.0.12 (released 2011-07-15)

This is a maintenance release. The following items were fixed and/or added:

• Mac OS X hosts: Lion fixes
• Solaris hosts: fixed preemption issue with Solaris 11 hosts (builds 166 and above)
• VBoxManage: more convenient configuration of storage controller attachments by automatically determining the port or device parameter when a storage controller has only one port or device per port (bug #9188)
• Storage: fixed possible data corruption under certain circumstances whith VHD and Parallels images (bug #9150)
• Storage: fixed access to CD/DVD images beyond 4GB when using the SATA controller (bug #8592)
• Floppy: make it possible to unmount a host floppy disk (bug #6651)
• Networking: fixed the problem with segmentation offloading when several VMs were transmitting at once
• 3D support: fixed GL_VERSION string for different locales (bug #8916)
• Sources: fixed USB 2.0 support using extension packs for non-official builds
• Solaris Additions: fixed automounting of shared folders (bug #8014)

VirtualBox 4.0.10 (released 2011-06-27)

This is a maintenance release. The following items were fixed and/or added:

• GUI: fixed disappearing settings widgets on KDE hosts (bug #6809)
• Storage: fixed hang under rare circumstances with flat VMDK images
• Storage: a saved VM could not be restored under certain circumstances after the host kernel was updated (bug #8983)
• Storage: refuse to create a medium with an invalid variant (for example Split2G with VDI; bug #7227)
• Snapshots: none of the hard disk attachments must be attached to another VM in normal mode when creating a snapshot
• USB: fixed occasional VM hangs with SMP guests (bug #4580)
• USB: proper device detection on RHEL/OEL/CentOS 5 guests (partial fix for bug #8978)
• ACPI: force the ACPI timer to return monotonic values for improve behavior with SMP Linux guests (bug #8511 and others)
• RDP: fixed screen corruption under rare circumstances (bug #8977)
• rdesktop-vrdp: updated to version 1.7.0
• OVF: under rare circumstances some data at the end of a VMDK file was not written during export
• Mac OS X hosts: Lion fixes (bug #8903)
• Mac OS X hosts: GNOME 3 fix
• Linux hosts: fixed VT-x detection on Linux 3.0 hosts (bug #9071)
• Linux hosts: fixed Python 2.7 bindings in the universal Linux binaries
• Windows hosts: fixed leak of thread and process handles
• Windows Additions: fixed bug when determining the extended version of the Guest Additions (4.0.8 regression; bug #8948)
• Solaris Additions: fixed installation to 64-bit Solaris 10u9 guests (4.0.8 regression)
• Linux Additions: RHEL6.1/OL6.1 compile fix
• Linux Additions: fixed a memory leak during VBoxManage guestcontrol execute (bug #9068)

VirtualBox 4.0.8 (released 2011-05-16)

This is a maintenance release. The following items were fixed and/or added:

• Mac OS X hosts: fixed incompatibility with recent Mac OS X versions in 64-bit mode (bug #8474)
• Mac OS X hosts: fixed incompatibility with hosts with more than 16 cores (bug #8389)
• Mac OS X hosts: fixed painting corruptions on a second monitor in 64-bit mode (bug #7606)
• GUI: restored functionality to set an empty host key to disallow any host key combination (4.0.6 regression; bug #8793)
• VBoxManage: added controlvm screenshotpng subcommand for saving the screenshot of a running VM in PNG format
• VBoxHeadless: fixed potential crash during shutdown (Windows hosts only)
• NAT: built-in services use the correct Ethernet addresses in Ethernet header and in ARP requests
• Host-only networking: fixed adapter reference counting
• E1000: fixed rare guest crashes with Linux SMP guests (bug #8755)
• SATA: fixed guest disk corruption under rare circumstances (only relevant for guests with more than 2GB RAM; bug #8826)
• Storage: fixed data corruption after a snapshot was taken with asynchronous I/O enabled (bug #8498)
• Floppy: several improvement
• HPET: another fix for time jumps (bug #8707)
• USB: removed assumption that string descriptors are null-terminated (Windows hosts only)
• 3D support: fixed a potential crash when resizing the guest window
• 3D support: fixed GNOME 3 rendering under Ubuntu 11.04 and Fedora 15
• Snapshots: fixed another bug which could lose entries in the media registry when restoring a snapshot (bug #8363)
• Shared Folders: don't stop mounting the other valid folders if one host folder is inaccessible (4.0.6 regression)
• Linux Additions: check whether gcc and make are installed before building kernel modules (bug #8795)
• Solaris Additions: added support for X.Org Server 1.10
• Guest Additions: fixed inappropriate Guest Additions update notification when using vendor-specific version suffixes (bug #8844)

VirtualBox 4.0.6 (released 2011-04-21)

This is a maintenance release. The following items were fixed and/or added:

• VMM: fixed incorrect handling of ballooned pages when restoring a VMM from a saved state
• VMM: don't crash on hosts with more than 64 cores / hyperthreads; implemented support for up to 256 host cores (except Windows hosts; bug #8489)
• VMM: fixed guru meditation for PAE guests running on hosts without PAE (bug #8006)
• VMM: fixed slow Linux guests with raw mode and recent guest kernels (bug #8726)
• GUI: support host key combinations (bug #979)
• GUI: fixed progress indicator (bug #7814)
• GUI: show the mouse pointer while the VM is paused if the USB tablet mouse emulation is used (bug #6799)
• GUI: adapt the snapshot folder as well when renaming a VM (bug #8469)
• GUI: persistently remember the last folders of the disk/DVD/floppy selectors
• GUI: never allow to start a VM with USB-2.0 activated if the proper extension pack is missing (bug #8182)
• GUI: fixed hang/crash when opening a file dialog in an non-existing folder (bug #8673)
• Snapshots: fixed a bug which could lose entries in the media registry when restoring a snapshot (bug #8363)
• Snapshots: allow snapshots to be stored in the VM directory
• 3D support: fixed a crash if a VM was forced to terminate (Windows hosts only; bug #7133)
• Storage: fixed memory leak (4.0 regression; bug #7966)
• Storage: fixed access to iSCSI targets over internal network
• Storage: fixed reading from disks with more than one snapshot for VHD and VMDK images with disabled host cache (bug #8408)
• Storage: fixed a possible hang during VM suspend after an I/O error occurred
• Storage: fixed a possible hang during VM suspend / reset (bug #8276, #8294)
• Storage: automatically create a diff image when attaching a streamOptimized VMDK image to a VM
• ATA/SATA: fixed automounting of virtual CD/DVD mediums with recent Linux distributions by correctly reporting the current profile as 'none' if no medium is present
• Buslogic: fixed emulation for certain guests (e.g. jRockit VE)
• Host-Only Networking: fixed interface creation failure on Windows hosts (4.0.4 regression; bug #8362)
• Host-Only & Bridged & Internal Networking: fix for processing promiscuous mode requests by VMs, defaulting to switch behaviour
• Host-Only Networking: fixed connectivity issue after resuming the host from sleep (bug #3625)
• Bridged Networking: support for interface bonding on Mac OS X hosts (bug #8731)
• NAT: fixed processing of ARP announcements for guests with static assigned IPs (bug #8609)
• VRDP: backward compatibility with VRDPAuth external authentication library (bug #8063)
• Shared Folders: don't fail to start a VM if a path is not absolute, for example when importing an OVF from a different host (bug #7941)
• Audio: fixed crash under certain conditions (bug #8527)
• USB: fixed a crash when plugging certain USB devices (bug #8699)
• HPET: fixed time jumps when reading the counter (bug #8707)
• OVF/OVA: automatically adjust disk paths if the VM name is changed on import
• OVF/OVA: fix export to slow medias
• OVF/OVA: automatically repair inconsistent appliances with multiple disks (bug #8253)
• rdesktop-vrdp: fixed an assertion triggered under certain conditions (bug #8593)
• Windows hosts: fixed occasional hangs during VM shutdown because sometimes COM was not properly uninitialized
• Mac OS X hosts: prevent the mouse from leaving the VM window while captured
• Mac OS X hosts: keep aspect ratio while resizing in scale mode (shift for old behaviour) (part of bug #7822)
• X11 hosts: fixed Yen key support (bug #8438)
• X11 hosts: fixed a regression which caused Host+F1 to pop up help instead of sending Ctrl+Alt+F1
• Linux hosts / Linux Additions: mangle IPRT symbols to allow installing VirtualBox inside a VM while the Guest Additions are active (bug #5686)
• Linux hosts / Linux guests: workaround for a bug in GLIBC older than version 1.11 leading to crashes under certain conditions (signed/unsigned problem with memchr on 64-bit machines)
• Solaris hosts: fixed a deadlock in event semaphores that could lead to unkillable VM processes
• Windows Additions: fixed Sysprep parameter handling
• Windows Additions: fixed spontaneous guest reboots under certain circumstances (4.0.2 regression; bugs #8406, #8429)
• Windows Additions: added auto logon support for locked workstations on legacy Windows versions
• Windows Additions: fixed driver bugcheck error when handling PnP messages (4.0 regression; bug #8367)
• Windows Additions: fixed memory leak in VBoxVideo
• X11 Additions: added support for X.Org Server 1.10 final
• Linux Additions: Linux kernel 2.6.39-rc1 fixes
• Linux Additions: improved auto-run support (bug #5509)
• Linux Additions: fix mouse support on SUSE 11 SP 1 guests (bug #7946)
• Solaris Additions: added support for X.Org Server 1.9
• Guest Additions: various bugfixes for guest control execution
• Webservice: use own log file, with log rotation to limit size

VirtualBox 4.0.4 (released 2011-02-17)

This is a maintenance release. The following items were fixed and/or added:

• VMM: fixed recompiler crashes under certain conditions (bugs #8255, #8319 and further)
• VMM: fixed running 64-bit guests on 32-bit host with nested paging enabled on AMD CPUs (4.0 regression; bug #7938)
• VMM: fixed timing issues / hangs for certain guests using the programmable interval timer (bugs #8033 and #8062)
• VMM: large page and monitoring fixes for live snapshots (bugs #7910, #8059, #8125)
• GUI: fixed error message when trying to exceed the maximum number of host network interfaces
• GUI: fixed saving of changes to the metadata of an existing snapshot (bug #8145)
• GUI: fixed rare crash on X11 hosts (bug #8131)
• GUI: when selecting a shared folder, start the file dialog in the users home directory (bug #8017)
• ExtPack: enforce the correct permissions which might be restricted by umask when creating directories (non-Windows hosts only; bug #7878)
• VBoxSDL: fixed crash when starting by specifying the VM UUID (4.0 regression; bug #8342)
• VBoxManage: allow savestate even if the VM is already paused
• VBoxManage: fixed modifyvm --synthcpu (bug #6577)
• VBoxManage: fixed hang when doing guestcontrol execute –wait-for exit and displaying process status on exit (bug #8235)
• VBoxManage: decreased CPU load during guestcontrol execute –wait-for exit/stdout while waiting for the guest process to terminate (bug #7872)
• VBoxManage: fixed list hostdvds/hostfloppies
• VBoxManage: fixed storageattach for host DVD drives and host floppy drives
• Metrics: introduced RAM/VMM base metric.
• Main: improved sanity check when taking a VM screen shot (bug #7966)
• Main: fixed a crash under rare circumstances if a VM failed to start
• Main: fixed attaching of immutable disk images (bug #8105)
• Main: fixed a crash at VM shutdown (bug #6443)
• Main: fixed incorrect handling of cross-referenced medium attachments (bug #8129)
• Settings: fixed truncating of big integer values (4.0 regression)
• Settings: properly store the ICH9 chipset type (bug #8123)
• Host-Only & Bridged Networking: fixed VBox DHCP server startup issue for Windows hosts (4.0 regression; bug #7905)
• Host-Only Networking: re-create vboxnetX interfaces after vboxnetadp.ko module reload on Linux and Darwin (bugs #5934, #6341)
• NAT: fixed an mbuf leak under rare circumstances (bug #7459)
• ACPI: don’t allow the guest to enter S4 by default and don’t announce S1 and S4 in the ACPI tables if disabled (bug #8008)
• Graphics card: made re-enabling disabled screens work correctly to prevent problems when X11 guests enter screen saving mode (bug #8122)
• Storage: fixed write errors with snapshots if the host cache is disabled (4.0 regression; bug #8221)
• ATA/SATA: fixed reset handling after ACPI suspend/resume
• BusLogic: fixed hang with SMP VMs
• Serial: another attempt to prevent lost characters during transmission (bug #1548)
• Linux hosts/guests: Linux 2.6.38-rc1 compile fixes
• Mac OS X hosts: fixed VBoxSVC crash when listing host interfaces without default gateway (64-bit hosts only; bug #7955)
• Solaris/Darwin hosts: fixed VM CPU execution cap
• X.Org guests: fixed a crash on X server restart (bug #8231)
• X.Org guests: support X.Org Server 1.10 pre-release and Ubuntu 11.04 Alpha.
• X.Org guests: Add EDID emulation in the graphics driver to prevent GNOME settings daemon changing the mode on login.
• X.Org guests: never send graphics modes to the host that older VirtualBox versions can’t handle.
• Linux Additions: fixed a memory leak in the shared folders code if a host link is not readable (bug #8185)
• Windows Additions: fixed handling of Security Attention Sequence (SAS) with VBoxGINA

VirtualBox 4.0.2 (released 2011-01-18)

This is a maintenance release. The following items were fixed and/or added:

• GUI: don't crash if a removable host drive referenced from the VM settings vanished
• GUI: fixed a crash when using the KDE4 Oxygen theme and clicked on the settings button (4.0 regression; bug #7875)
• GUI: properly warn if the machine folder cannot be created (bug #8031)
• GUI: several fixes for multimonitor X11 guests
• ExtPack: don’t make the installer helper application suid root (Linux .deb/.rpm packages only)
• ExtPack: improved user experience on Vista / Windows 7 when installing an extension pack
• ExtPack: fixed issue with non-ascii characters in the path name during installing an extension pack (bug #7917)
• ExtPack: fixed SELinux issues on 32-bit Linux hosts
• VBoxManage: Host-only interface creation and removal is now supported for all platforms except Solaris (bug #7741)
• VBoxManage: fixed segmentation fault when removing non-existent host-only interface
• Storage: fixed possible crashes with VMDK/VHD images with snapshots and async I/O (4.0 regression)
• Storage: don’t eject the physical medium if a DVD/CDROM/floppy drive is detached from a VM (bug #5825)
• Storage: be more robust when a faulty guest sends ATA commands to an ATAPI device (bug #6597)
• Parallels: fixed deletion of the image during suspend, pause or power off (4.0 regression)
• Bridged networking: fixed host kernel panic when bridging to devices with no TX queue (4.0 regression; Linux hosts only; bug #7908)
• NAT: port-forwarding rule registration respects protocol parameter (bug #8094)
• E1000: fixed PXE boot issues with WDS (bug #6330)
• Virtio-net: fixed the issue with TX performance in some Linux guests
• ICH9: fixed VM crash (software virtualization only; bug #7885)
• VGA: fixed VESA screen issue (4.0 regression; bug #7986)
• Shared Folders: fixed parameter parsing when creating symbolic links, fixes 32-bit/64-bit bitness issue (bug #818)
• Main: fixed crash under rare circumstances due to an invalid logging string (4.0 regression)
• Main: improve error information propagation for errors preventing a VM start
• Main: fixed problems with snapshots and non-ASCII characters in machine paths (bug #8024)
• Webservice: now listens to localhost by default as documented (bug #6067)
• Settings: do not fail loading machine settings if removeable drive attachment (host drive or image) cannot be found; with 4.0 this is much more likely when machines are moved from one host to another
• Settings: fixed issue that changing a snapshot name or description was not saved to machine XML
• OVF/OVA: fixed import of files created by other OVF tools (bug #7983)
• rdesktop-vrdp: fix a crash during USB device enumeration (bug #7981)
• Linux hosts: fixed a crash during USB device enumeration.
• Linux hosts: try a bit harder to allocate memory (bug #8035; 4.0 regression)
• Guest Additions: fixed parsing of parameters for guest control in VBoxService (4.0 regression; bug #8010)
• Windows Guest Additions: automatic logon on Windows Vista/Windows 7 now supports unlocking previously locked workstations

VirtualBox 4.0.0 (released 2010-12-22)

This version is a major update. The following major new features were added:

• Reorganization of VirtualBox into a base package and Extension Packs; see chapter 1.5, Installing VirtualBox and extension packs, see the manual for more information
• New settings/disk file layout for VM portability; see chapter 10.1, Where VirtualBox stores its files, see the manual for more information
• Major rework of the GUI (now called “VirtualBox Manager”):
  • Redesigned user interface with guest window preview (also for screenshots)
  • New “scale” display mode with scaled guest display; see chapter 1.8.5, Resizing the machine’s window, see the manual for more information
  • Support for creating and starting .vbox desktop shortcuts (bug #1889)
  • The VM list is now sortable
  • Machines can now be deleted easily without a trace including snapshots and saved states, and optionally including attached disk images (bug #5511; also, VBoxManage unregistervm --delete can do the same now)
  • Built-in creation of desktop file shortcuts to start VMs on double click (bug #2322)
• VMM: support more than 1.5/2 GB guest RAM on 32-bit hosts
• New virtual hardware:
  • Intel ICH9 chipset with three PCI buses, PCI Express and Message Signaled Interrupts (MSI); see chapter 3.4.1, “Motherboard” tab, see the manual for more information
  • Intel HD Audio, for better support of modern guest operating systems (e.g. 64-bit Windows; bug #2785)
• Improvements to OVF support (see chapter 1.12, Importing and exporting virtual machines, see the manual for more information):
  • Open Virtualization Format Archive (OVA) support
  • Significant performance improvements during export and import
  • Creation of the manifest file on export is optional now
  • Imported disks can have formats other than VMDK
• Resource control: added support for limiting a VM’s CPU time and IO bandwidth; see chapter 5.8, Limiting bandwidth for disk images, see the manual for more information
• Storage: support asynchronous I/O for iSCSI, VMDK, VHD and Parallels images
• Storage: support for resizing VDI and VHD images; see chapter 8.21, VBoxManage modifyhd, see the manual for more information.
• Guest Additions: support for multiple virtual screens in Linux and Solaris guests using X.Org server 1.3 and later
• Language bindings: uniform Java bindings for both local (COM/XPCOM) and remote (SOAP) invocation APIs

In addition, the following items were fixed and/or added:

• VMM: Enable large page support by default on 64-bit hosts (applies to nested paging only)
• VMM: fixed guru meditation when running Minix (VT-x only; bug #6557)
• VMM: fixed crash under certain circumstances (Linux hosts only, non VT-x/AMD-V mode only; bugs #4529 and #7819)
• GUI: add configuration dialog for port forwarding in NAT mode (bug #1657)
• GUI: show the guest window content on save and restore
• GUI: certain GUI warnings don’t stop the VM output anymore
• GUI: fixed black fullscreen minitoolbar on KDE4 hosts (Linux hosts only; bug #5449)
• BIOS: implemented multi-sector reading to speed up booting of certain guests (e.g. Solaris)
• Bridged networking: improved throughput by filtering out outgoing packets intended for the host before they reach the physical network (Linux hosts only; bug #7792)
• 3D support: allow use of CR_SYSTEM_GL_PATH again (bug #6864)
• 3D support: fixed various clipping/visibility issues (bugs #5659, #5794, #5848, #6018, #6187, #6570)
• 3D support: guest application stack corruption when using glGetVertexAttrib[ifd]v (bug #7395)
• 3D support: fixed OpenGL support for libMesa 7.9
• 3D support: fixed Unity/Compiz crashes on natty
• 2D Video acceleration: multimonitor support
• VRDP: fixed rare crash in multimonitor configuration
• VRDP: support for upstream audio
• Display: fixed occasional guest resize crash
• NAT: port forwarding rules can be applied at runtime
• SATA: allow to attach CD/DVD-ROM drives including passthrough (bug #7058)
• Floppy: support readonly image files, taking this as the criteria for making the medium readonly (bug #5651)
• Audio: fixed memory corruption during playback under rare circumstances
• Audio: the DirectSound backend now allows VMs to be audible when another DirectSound application is active, including another VM (bug #5578)
• EFI: support for SATA disks and CDROMs
• BIOS: reduce the stack usage of the VESA BIOS function #4F01 (Quake fix)
• OVF/OVA: fixed export of VMs with iSCSI disks
• Storage: Apple DMG image support for the virtual CD/DVD (bug #6760)
• Linux host USB support: introduced a less invasive way of accessing raw USB devices (bugs #1093, #5345, #7759)
• Linux hosts: support recent Linux kernels with CONFIG_DEBUG_SET_MODULE_RONX set
• Guest Additions: Shared Folders now can be marked as being auto-mounted on Windows, Linux and Solaris guests
• Linux Additions: Shared Folders now support symbolic links (bug #818)
• Linux Additions: combined 32-bit and 64-bit additions into one file
• Windows Additions: automatic logon on Windows Vista/Windows 7 is now able to handle renamed user accounts; added various bugfixes