Auto-resize broken - Win10 Host & Guest

[LukeFranky]

I have a problem where my windowed guest will revert to 800x600 or a similar default resolution on the primary monitor after returning to my host after the screensaver comes on. The secondary screen stays as is.

The guest mouse is also becomes out of sync with the host. If I move the host mouse to the far right of the primary screen the guest will be closer to the middle. If I move the mouse to the left each pointer will be much closer together but still not in tune.

I normally work in maximized windowed mode. By that I mean the guest will be within a VirtualBox window but that will be maximized take up the most amount of space without hiding my host's taskbar.

This problem is becoming a show stopper. The only solution so far has been to restart the host entirely. It is starting to happen once or twice a day (I use VBox alot).

Things I have tried:

• Restarting guest.
• Resizing the VirtualBox windows.
• Minimizing the VirtualBox.
• Re-installing guest additions.
• Switch to fullscreen and back.

[LukeFranky]

Screenshot of primary display

[LukeFranky]

Now restarting the host doesn't help. The VM starts up at 1024 x 768.

[Frank Mehnert]

Please attach a VBox.log file of such a VM session!

[LukeFranky]

This is now happening to my co-worker's host machines as well. Often occurs after the screensaver has been active.

[Frank Mehnert]

Sorry, you attached the wrong log files. The VBox.log file I'm after can be found in the VM selector menu / Machine / Show Log ...

[Mihai Hanor]

I have the same problem with my Windows 10 VM.

[Malcolm Watt]

I had a similar issue with my Windows 10 Host and Ubuntu 14.04 Guest.

A temporary fix was to remove the guest additions iso from the controller with the machine off, and to start the machine and reinsert guest additions. Upon reinsertion it prompted for re-installation, which I accepted. Once the process was complete I rebooted and re-sizing worked.

It should be taken into consideration that this is affecting Linux guests as well.

[Mihai Hanor]

I've recompiled and installed the Guest Additions 5.0.20 with changeset 59518 rolled back, on my Windows 10 guest and the problem dissapeared. Windows 8.1 (as guest) shows the same problem on my Windows 10 host. The last release version of GA that doesn't show this problem is version 5.0.14

As a workaround, using the official GA binaries, you can go to Display settings -> Advanced settings, after the failed resize, and you will find the resolution in the list, the one that was supposed to be set by the Guest Additions.

[CoDEmanX]

I'm seeing something similar after updating to v5.0.20 r106931 (VirtualBox as well as Guest Additions), Windows 10 Pro 64bit as Host as well as guest:

• the resolution is not automatically adjusted to the window size
• it also stays at 1152x864 when I go to fullscreen mode
• automatic resize is enabled however (also restarted after installing the guest additions)
• I can manually adjust the resolution in the guest up to the window size, which means I need to go to fullscreen mode in order to make it the host monitor size of 1920x1080
• If I go from full HD fullscreen mode back to windowed mode, the resolution is automatically reduced - but it doesn't work the other way around (enlarge)

[sunlover]

This should be fixed in guest additions 5.1.x r108965+ and 5.0.x r108966+

Please download additions from https://www.alldomusa.eu.org/wiki/Testbuilds

mhanor, the fix addresses the problem, which happens with changeset 59518.

Please test. Thanks!

[Mihai Hanor]

I have tested GuestAdditions_5.1.3-108967 and guest auto-resizing works fine.

[Frank Mehnert]

Fix is part of 5.1.4.