"Auto-resize guest display" doesn't resize guest after boot

[nvivo]

In VB 1.5.6, if I had the "Auto-resize guest display" enabled, the resolution of the guest was changed right after boot. On 1.6.0 (and continues on 1.6.2), the option is set, but the machine boots with a lower resolution. Hots+G doesn't work either, I must change the size of the window for VB to detect the resolution is different.

In my case, my host resolution is 1280x1024 on linux. When I boot a XP VM, it boots at 1152x864, although the window is maximized and has a large border. After restore/maximize the guest window, it goes to full size (1264x881 in my case).

[Frank Mehnert]

Did you read section 9.12 of the user manual (version 1.6.2 please)? Sounds like the host does not allow bigger resolutions.

[nvivo]

I set the "GUI/MaxGuestResolution" to "any" as chapter 9.12 suggests and it seems to solve the problem.

Still, that doesn't make sense. The help says: "...they will not be allowed to use screen resolutions greater than the host's screen size unless the user manually resizes..."

I don't want a resolution bigger than my host screen size. The size is actually smaller. I just want the resolution of the guest to be auto resized as the "Auto-resize guest display" suggests, and if the screen is maximized, that option is set and my guest is smaller than the current guest window, that should resize the window.

The Help follows saying "This behavior is what most users will want..." I believe the behavior would be "does not start the virtual machine with a resolution that would not fit the host screen". But the way it is since 1.6.0 seems to make regular users to always restore/maximize the window everytime the machine is turned on.

[Brian Mury]

I have been having the same problem, it also started with 1.6 (worked fine with 1.5.6). I set MaxGuestResolution to 1272x881, which is the resolution of the guest display when the window is maximized, and it now works as expected.

[dmjones500]

I have similar problems with version 2.0.6 (Host: Ubuntu 8.10, Guest: Win XP). The problem manifests when I switch from using my laptop's widescreen display to using an 4:3 external monitor. Virtualbox seems to think the resolution hasn't changed, and leaves the guest OS in widescreen-mode.

I'll try the "GUI/MaxGuestResolution" trick and will report back. However, it seems to me like VirtualBox should double-check the current host resolution before starting up a guest.

[dmjones500]

My experiments with "GUI/MaxGuestResolution" have confirmed my suspicions - VirtualBox is not successfully checking the host resolution when starting a guest operating system.

Ironically, when "GUI/MaxGuestResolution" is at its default setting, some kind of resolution checking _is_ being performed, as VBox can detect when the proposed resolution is too large for the host screen.

[Frank Mehnert]

There is nothing ironically. The guest additions will check if the host 'likes' a dedicated video mode. It might be that this check is not done when a video mode is set through the normal BIOS (as done by the boot loader).

[dmjones500]

Well, perhaps I have the wrong idea, but let me explain my thinking:

My laptop has a wide-screen display. Suppose I switch off my laptop and attach it to a docking station with an external monitor. When my machine boots up again it uses the external monitor and my resolution changes; it's no longer widescreen. When I start up VirtualBox, the change in resolution does not appear to be noticed - the guest OS will only fill up a widescreen-sized portion of the entire window: ​screenshot. If I unmaximise and then maximise the VirtualBox window, the Guest OS will correctly resize itself to my screen ​screenshot.

So it appears that VirtualBox is not recognising the different resolution. However, let me explain why I think the "GUI/MaxGuestResolution" _is_ working:

If I reboot my machine, whilst still attached to the docking station and monitor, VirtualBox will "remember" that my resolution is different and will start up at the correct resolution. Now, if I restart my computer and it's no longer attached to the monitor, the resolution becomes smaller and widescreen again. VirtualBox _does_ cope with this nicely, and doesn't accidentally display the larger non-widescreen resolution -> it recognises that my resolution has become smaller.

Any thoughts?

[dmjones500]

Actually, there is another possibility here: it seems like the correct resolution for my external monitor is applied automatically after I log into Ubuntu. The login screen is shown in a distorted manner, suggesting Ubuntu hasn't yet determined that my resolution has changed.

Is it possible that VirtualBox is determining the current resolution prior to me logging in, i.e. perhaps when the kernel module is first loaded?

/shot in the dark

[finex]

Could this ticket be considered as a duplicate of ​http://www.virtualbox.org/ticket/5372 ?

[Michael Thayer]

No, I don't think this is the same. Out of interest, is this still a problem for the original reporter/commenters?

[Florian]

to me, this sounds like a duplicate...