I've been using a PGP virtual disk for awhile on my old Windows 7 computer. I just bought a Windows 8.1 computer, and transfered my PGP virtual disk to my new computer. I found my old serial number, downloaded the PGP Desktop software, and installed it on the new computer. Just about everything works great--I can mount and unmount the old virtual disk no problem.
However, my virtual disk unmounts automatically after 2 minutes of inactivity (or when I put my computer to sleep/close my laptop.) I had disabled this setting on my old computer, because I'd like the disk there during an entire session of using my laptop, and I don't want to have to worry about it unmounting every few minutes just because I don't happen to use files from the virtual disk every few minutes.
On Windows Explorer, I right click on the mounted disk, go to the PGP Desktop submenu, and click "Edit Disk Properties." That opens up the PGP desktop software, and there is a box checked that says "Unmount when inactive for 2 mins." However, this box is greyed out, and there is no way for me to uncheck it. This option was disabled on my old computer, but now it's automatically enabled, and I'd really like to be able to change it so that it's not unmounting every few minutes.