One of my users has had a problem in the past when printing documents from Office 2012. After attempting to print, she got the message that the printer could not be found. Apparently, the cause of this was Office 2012, which would prevent printing after it detected a problem.
I found a solution in the following link: https://support.microsoft.com/en-us/help/983035/how-to-prevent-office-2010-from-disabling-printers . I added the registry key "DisablePrintFeaturesOnCrash" under HKEY_CURRENT_USER\Software\Microsoft\Office\14.0\Common\General and set it to 0, which seemed to solve the problems she was having.
Flash forward a couple of months, and I got a call from her telling me that the problem had resurfaced. After checking the registry, I found out that the registry key was gone. I added it again, and she could print again.
A few days later however, the registry key has disappeared again! She herself cannot remove the key (she can't access the registry), and none of my colleagues has touched that computer in weeks.
What could possibly remove that key? Is there a way to find out what process removed that key? And is it possible to prevent deletion of the key?