Dual monitor setup on host: guest window rendering issues on 2nd monitor

[VBoxer]

Configuration: Host: Mac OS X, 10.6 Guests: Win7, Linux; each one configured with 1 guest monitor

Steps to reproduce:

1. Open a guest window on the 1st monitor.
2. Drag guest window to the 2nd monitor (if it fails at the first attempt, try again)
3. Click somewhere on the 1st monitor.

Expected result: Clicking on the first monitor has no impact to the guest window on the 2nd monitor.

Actual result: The guest window sometimes turns black. It is not redrawn automatically, only if the user moves the mouse or clicks somewhere in that window or moves some windows in the guests foreground.

It's always reproducible with Windows 7 guest, and almost always with Linux (LXDE desktop), with Guest Additions installed. It's not reproducible on a Linux KDE desktop with no Guest Additions installed.

The vbox.log files don't contain any entries from the time the error occured. Let me know, if you need more information.

[Paul Colin]

Replying to VBoxer:

Config: Host= Mac OSX 10.6.8 - Guest = Win XP pro. Since more then a yaer, I use this to work with Microstation on 2 monitors, without any problem at all. Accepted invitation to upgrade to VBox 4.2.4 (October 26th). Since the it is impossible to use the 2nd monior. Hovering over it with the pointer "paints" parts of the screen; clicking on a window, makes it visible. But as soon as the pointer moves back to the 1st screen, the 2nd gets dark again.

Downgraded to version 4.1.4 r 7740 to obtain a second usable screen again, however without loading the guest additions. Not quite sure but I had the impression that loading guest additions when an earlier version of VBOX runs, jeopardizes the second screen again. Experimented on version 4.2.4 with different sizes of RAM and video RAM, with no avail.

Configuration: Host: Mac OS X, 10.6 Guests: Win7, Linux; each one configured with 1 guest monitor

Steps to reproduce:

1. Open a guest window on the 1st monitor.
2. Drag guest window to the 2nd monitor (if it fails at the first attempt, try again)
3. Click somewhere on the 1st monitor.

Expected result: Clicking on the first monitor has no impact to the guest window on the 2nd monitor.

Actual result: The guest window sometimes turns black. It is not redrawn automatically, only if the user moves the mouse or clicks somewhere in that window or moves some windows in the guests foreground.

It's always reproducible with Windows 7 guest, and almost always with Linux (LXDE desktop), with Guest Additions installed. It's not reproducible on a Linux KDE desktop with no Guest Additions installed.

The vbox.log files don't contain any entries from the time the error occured. Let me know, if you need more information.

[VBoxer]

This sounds like a bug in the Guest Additions. Can you create a snapshot and test with the 4.1.4 Guest Additions, please? If we knew that works we could go back to the older version. Thank you in advance.

[Pietro Braione]

I also have the same issue, with some minor differences. My host is a Macbook pro (Core2 duo 2,66 GHz) with OSX 10.6.8 in 32-bit mode, and I have the latest version of Virtualbox (4.2.4). In my case the issue arises both with Ubuntu 12.04.1 LTS (with Unity) and Windows 7 guests with one guest monitor. When the guest window is on the external monitor, it turns black in even more situations than VBoxer - notably, when I click on the guest window itself. Moreover, it does not really turn black, but rather it reverts the graphic content of the guest window to the one it had when I dragged it on the external monitor. I can confirm that by hovering the mouse cursor over the guest window, or by dragging some guest os gui item, or by selecting, etc., the guest os partially redraws the correct graphic content (but it's quite useless because the screen goes nuts as soon as I click anything). If I drag back the guest window to my laptop's screen everything works fine. All this happens also when I activate the full screen mode, and both with and without the guest additions. Same issue with previous (4.1.4, if I do not remember bad) Virtualbox release.

All in all it is a pity. My routine is using Spaces + full-screen mode for viewing my guests on the big, external screen. It has always worked very well until now.

[Paul Colin]

Replying to VBoxer:

This sounds like a bug in the Guest Additions. Can you create a snapshot and test with the 4.1.4 Guest Additions, please? If we knew that works we could go back to the older version. Thank you in advance.

It took me some reshuffling to secure a zillion of CAD-files that reside in the Vitual Machine. Also did I make a clone of my operating system with CCC. I starded Virtualbox, version 4.1.4 r 7740 as explained here above - on a Mac OS X 10.6.8 (10K549) Kernel :10.8.0 - and installed the Guest Additions. The window that popped up told me I was installing version 4.1.14. During installtion I was repeatedly requested for replacement of NEWER files, thoug I did definitely not install Guest Additions on the copy of the virtual Machine on subject. However, the results are exactly the same: The dual monitors are working correctly. If my assumption is correct that Guest Additions don't change a single bit in the Host OS, this conclusion sounds sane.

[VBoxer]

Thank you, Orka, for the advice to downgrade to VirtualBox 4.1.4. It was a bit tricky and I write my experiences to let others think twice before they do the same.

1. Starting some VMs failed with error messages like this:

Unsupported version 14 of data unit 'cpum' (instance #1, pass 0xffffffff) (VERR_SSM_UNSUPPORTED_DATA_UNIT_VERSION). Error Code: NS_ERROR_FAILURE (0x80004005) Component: Console Interface: IConsole {1968b7d3-e3bf-4ceb-99e0-cb7c913317bb}

To solve and further avoid them I had to upgrade back and shutdown the guest systems properly. Just saving their current state is not enough. When trying to revert to former snapshots I had this problem again - so upgrade again, delete all snapshots, downgrade again.

2. It's crucial to restart the host system after uninstalling VirtualBox. This will unload the former Virtualbox kernel drivers on the OS X host. Sometimes this is also necessary after installing the other VirtualBox version. To comply with Apples human interface guidelines Oracle should handle this better and force the user to restart the system as rarely as possible.

3. When I finally managed to have VirtualBox 4.1.4 running on the guests the bug with the visual artifacts on the second screen was really gone away. Only the KDE4 guest showed some drawing issues.

Unfortunately I couldn't access the shared folders from the Ubuntu guests anymore due to a missing DKMS kernel module (that's specific to Linux guests). With a heavy heart I decided to choose the lesser evil and upgrade to VirtualBox 4.2.6.

At the end the visual artifacts are still here and I lost all snapshots. I really hope Oracle will fix this bug in one of the next versions.

However, I don't blame you, Orka. You tried to help and I thank you for this.