If the virtual machine is VirtualBox based, it may have troubles with the graphics virtualization (issues related to VBoxDispD3D-x86.dll)
To solve this, run Boxcryptor in software rendering mode as described here:
- Exit Boxcryptor if running.
- open Boxcryptor.exe.config (can be found in the installation folder e.g.
C: \Program Files (x86)\Boxcryptor\Boxcryptor.exe.config).
<add key = "ForceSoftwareRendering" value = "true" />).
- Start Boxcryptor again.