Same problem here. Could not find any solution either. I just uninstalled X and reinstalled 9.4
I was having this issue today on a co-worker's machine.
However I found a solution thanks to brian.hart.
Go into your registry editor (Run >> regedit)
Go to Hive [HKEY_LOCAL_MACHINE\Software\Policies\Adobe\Acrobat reader\10.0\FeatureLockDown]
Right click >> go to New >> DWORD
Give it the name "bProtectedMode"
Hit okay. Close Regedit. Win.
You may have to restart the computer. I didn't have to though.
I almost forgot. I should mention that Reader X allows you to turn Protected Mode on or off in the Preferences menu, however my Reader was closing even when trying to select an option from the menu.
The way above is a work around to that problem, so first try to change it in Edit>>Preferences.
Thanx CravenIT for your advice. I had the same problem as katJKOMZ and your advice solved my problem.
Thanks a lot, finally! This worked! phew!