Microsoft has begun patching files on Windows XP and Vista without users knowledge, even when the users have turned off auto-updates.
In recent days, Windows Update (WU) started altering files on users' systems without displaying any dialog box to request permission. The only files that have been reportedly altered to date are nine small executables on XP and nine on Vista that are used by WU itself. Microsoft is patching these files silently, even if auto-updates have been disabled on a particular PC.
Read the entire article about this here.
I was talking to my son about this tonight and he said that when he went to the pharmacy on base today to get a prescription filled that the computers updated and restarted and it resulted in a delay. Now he won't be able to get his medicine until tomorrow.