DT Ultra hung on ISO mount with device addition

[oder2]

Just now, I have DT Ultra release stuck with "Mount..." progress popup animating while I was trying to mount an ISO via main menu. I had one virtual device installed but it already contained another image mounted, so one more device had to be auto-added. And it was added according to the hardware detection sound that was played, but the mount process seems to be stuck and never ends after that.

Windows 8.1 x64

[oder2]

After I killed DTUltra.exe process with Task Manager, on next application start there were no virtual drives at all. When I tried to mount the same ISO once again, DTUltra terminated on exception.