7.012r159484 Guest Additions crash Windows 7 Guest

[jbh]

Host machine is Ubuntu 20.04 LTS. I upgraded from VirtualBox 6.1.42 to 7.0.12r159484. Windows 7 x64 guest booted up and appeared to run well with no issues using 6.1.42r155177 Guest Additions. I upgraded the guest additions after being prompted to do so. Upon reboot, during the Windows 7 splash screen, the guest went into Windows recovery/repair mode. Windows recovery could not repair the installation, and could not revert to any previous restore points, so I booted to safe mode and removed the guest additions. I was able to reboot into normal mode without guest additions, but could not get any mouse functionality in the guest, which made navigation difficult.

I used Remote Desktop to access the guest to install the latest test build Guest Additions 7.0.13r160845, but the same behavior occurred upon reboot, as the guest went into Windows recovery mode. I again uninstalled the Guest Additions via safe mode, but could not get any mouse functionality in the guest in normal mode without guest additions, so I restored the guest from a backup, and am now running successfully again with 7.012r159484 host and 6.1.42r155177 guest additions.

For reference, I have a Windows 10 host running 7.0.10r158379 that can run a Windows 7 x64 guest with 7.0.10r158379 Guest Additions installed.

[zeeh1975]

Same with VirtualBox 7.0.12r159484, host Windows 10 x64 (10.0.19045.3803), guest Windows 7 x32 (6.1.7601).

[jbh]

Tonight, I ended up reverting back to VirtualBox 6.1 host. The Windows 7 guest mentioned above is actually my home server, and file transfer speed from the guest became extremely slow at best to regularly failing at worst. After reinstalling VirtualBox 6.1, all is back to normal. I am using a bridged adapter to a second network card in the Win 7 guest.

I don't know what is going on with VirtualBox 7. I also noticed that sound wasn't working in that Win 7 guest either. Maybe the 7.0 Guest Additions are needed for it to function properly. Whatever the case, I can't use 7.0.

[caporeira]

After installation Window 7 as virtual machine, I have no rights to install Additional Guests? How to fix it?