Windows on Windows remote desktop causes Qt5GuiVBox.dll to use a null pointer

[PHolder]

More details and logs can be found at ​https://forums.virtualbox.org/viewtopic.php?t=110355

In summary, I leave remote desktop connected to the remote machine but minimize it locally until I want to check in later. The remote desktop that is the host will invoke the screen lock after 10 minutes or so. When things work normally, I bring the remote desktop client up and enter my password into the screen lock, and then can use the VM. On some occasions (roughly once or twice a week) while I was away something in the process seems to cause Virtual Box some grief. When I bring up the minimized remote desktop session, on top of the logon screen there will be a dialog box with an error message. Here's the most recent one (others are in my forum posts):

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VirtualBoxVM.exe - Application Error
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The instruction at 0x00007FFE23836DB2 referenced memory at 0x0000000000000000. The memory could not be written.

Click on OK to terminate the program
Click on CANCEL to debug the program
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OK   Cancel   
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In the case where I get this message, the VM seems to keep executing, until I click the OK button, at which point it forcefully closes. In other cases, I don't get such a dialog, and I just come back to find the VM has gone missing.

For the above dialog, looking in the reliability monitor finds:

Faulting application name: VirtualBox.exe, version: 7.0.12.9484, time stamp: 0x652832d4
Faulting module name: Qt5GuiVBox.dll, version: 5.15.2.0, time stamp: 0x606c96f9
Exception code: 0xc0000005
Fault offset: 0x0000000000066dc8
Faulting process id: 0x1f5c
Faulting application start time: 0x01da10517c3e244f
Faulting application path: C:\Program Files\Oracle\VirtualBox\VirtualBox.exe
Faulting module path: C:\Program Files\Oracle\VirtualBox\Qt5GuiVBox.dll

May be somewhat related to https://www.virtualbox.org/ticket/21890 in that Windows Remote Desktop seems to connect/disconnect the screen some way when the remote screen locks.

[fth0]

You're reporting two crashes, one in the VirtualBox Manager (VirtualBox.exe) and one in the VM (VirtualBoxVM.exe). Since the latter is a duplicate of #21931, which has been worked on lately:

Please try the VirtualBox test builds 7.0.13r160845 or newer.