Aero/transparency on Windows Vista no longer working with VirtualBox 6.0.0 r127566

[Rutger van Bergen]

I performed the following steps:

• On my Windows 10 Professional (version 1809, build 17763.253) host, I upgraded VirtualBox 5.2.22 to 6.0.0 r127566
• In an exisiting Windows Vista Ultimate guest, upgraded VirtualBox Guest Additions from 5.2.22 to 6.0.0.
• During the Guest Additions upgrade, as before, I selected experimental 3D accelleration and chose "no" when asked if I wanted basic Direct3D support.
• Restarted the guest when prompted.

After these steps:

• Aero/transparency effects no longer work in the Vista guest (and Aero is no longer offered as an option within Windows Vista) where they did with VirtualBox 5.2.22 and earlier 5.2 versions.
• The VBox.log indicates that 3D is enabled and available, and contains no apparent indications of errors.

[Rutger van Bergen]

Just noting that with version 6.0.2 r128162 (both VirtualBox and the Guest Additions), the issue remains. Furthermore, I've noticed that when I run the Windows System Assessment Tool on the guest, it shows a number of Bad Image dialogs, stating that "C:\Windows\system32\VBoxDispD3D.dll is either not designed to run on Windows or it contains an error."

[Socratis]

There is a discussion in the forums: ​https://forums.virtualbox.org/viewtopic.php?f=2&t=91314 which is dealing with the same issue. I'm going to "tie" the two, since the ticket here and the discussion in the forums are the only two reports on Vista.

So, please let's continue this discussion in the forums until we figure out what's going on...

[Rutger van Bergen]

I forgot to mention in the original report that the guest is a 64 bit version of Windows Vista. This appears to be relevant to (the reproduction of) the issue.

[Rutger van Bergen]

Problem remains in version 6.0.4 as well.

[Rutger van Bergen]

Problem remains in version 6.0.6.

[Rutger van Bergen]

Problem remains in version 6.0.8.

[mulder2@…]

Problem remains in version 6.0.10.

[Rutger van Bergen]

For me, in version 6.0.10, the issue is resolved for the 64-bit version of the Vista Guest Additions. Running the Windows System Assessment Tool does not yield any errors. Also, the Windows Experience Index is much higher than with the 5.2 Guest Additions (it increased from 2.9 to 4.5).

[snowcool776]

Can somebody merge this with 19036 please? Somehow this was there, but is older.