The mystery continues: Why are Windows machines automatically updating themselves?

A (slight) update on last week's report that some Windows users are seeing their Vista PCs automatically update themselves and reboot.

From Nate Clinton, a Microsoft Update Program Manager, via the Microsoft Update Product Team blog:

"We have been hearing some questions recently regarding Tuesday’s update release changing automatic updating settings. We have received some logs from customers, and have so far been able to determine that their AU settings were not changed by any changes to the AU client itself and also not changed by any updates installed by AU.

"We are still looking into this to see if another application is making this change during setup with user consent, or if this issue is related to something else. We are continuing the investigation, and as I have more information I will update this post.

"If you are running into this issue, your help would be greatly appreciated. You can contact support, and they can walk you through the steps necessary to provide logs and other useful data."

So, it doesn't seem to be Automatic Update (AU) or the patches themselves at fault. So what caused last Past Tuesday's patches to be installed automatically and machines to be rebooted for a group of users who had chosen not to allow automatic installation of patches -- as originally reported on the AeroXperience site? It's still not clear whether it is Vista only (or also XP) that is affected and whether Windows Software Update Services (WSUS) users have seen the same problem.

More to come when there's new info to share.

Update (3:30 p.m. EST): I've gotten notes from a few users saying that XP is also affected. Microsoft officials had declined to comment on which versions of Windows were affected by this update glitch. So far it seems to be XP and Vista. Other users of other Windows releases out there having the same trouble?

(74 actualitzacions de seguretat per instal·lar. Image by xcaballe. CC 2.0)