How to reproduce:
1. Run ReactOS on safe Mode (or run in normal, but you must change commandline in step 3);
2. Insert the VBox Guest Additions disk into VM;
3. run cmd.exe, go to the disk root dir and type the command VBoxGuestAdditions.exe /l (This letter is 'L', not 'I'!);
4. The install process will halt and you can read the flickering log;
5. In this log will be the entry '(3) ERROR: 3758096907 - RETURN UpdateDriverForPlugAndPlayDevices.' (but the device is present on this VM)
This error is also detectable without these commandline args, but the VBox Guest Additions installer will simply ignores it. (you still may see it in a fast scrolling install log).
The attachments contains this scrolling log (instlog.txt), drivers install log (drvinstlog.txt) and overall log created by installer (overall.txt)