Tech Tip: Get a list of hot fixes from the registry

Microsoft has released numerous patches for its various operating systems, and it's difficult to keep track of what's been installed on a server, especially if you're not using some sort of patch management application.

Windows NT keeps track of this information in the following registry key:

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows NT\CurrentVersion\Hotfix

The Hotfix registry key has subkeys with names that correspond to the Microsoft Knowledge Base article in which the hot fix was released. For example, HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows NT\CurrentVersion\Hotfix\Q246009 is associated with the SP6a hot fix.

Inside the individual keys are values that provide information about the hot fix. However, not every key includes this information. Here's the information that's related to the SP6a hot fix:

"Installed"=dword:00000001 "Comments"="Windows NT 4.0 Hotfix: Service Pack 6 Re-release" "Backup Dir"="" "Fix Description"="Windows NT 4.0 Hotfix: Service Pack 6 Re-release" "Installed By"="" "Installed On"="" "Service Pack"=dword:00000006 "Valid"=dword:00000001


Some years ago, I had what seemed to be an insurmountable computer glitch that would not go away. That was on Windows XP Home. I called Microsoft and it was an easy fix. There was a corrupted file that had to be replaced according to the Tech. He told me where to find it and how to replace it. There was an entire backup directory with replacement files that apparently are essential replacements if corrupted. I have not seen this directory in Windows vista or 7 (yet). I wondered if anyone else has or has run into this situation. I have used SFC to replace corrupted system files, (at least this is what worked at the time).