KB841873, the fix applied via Windows Update recently as a result of Microsoft Security Bulletin MS04-022, has been shown to cause Windows Task Scheduler to cease functioning on some computers.
If you rely on Windows Task Scheduler to perform backups, or other critical operations, and you have recently updated your computer with the critical fixes provided by Microsoft, I recommend that you check to see if you task scheduler jobs have actually been running. If any of the entries have a status of “Could not start” – then you might have this problem (or you’ve just not configured task scheduler correctly!)
The fix I found was to uninstall KB841873, followed by resetting the “run as” password for every entry in task scheduler.
Note that this problem has been shown to occur on some Windows 2000 and Windows XP machines where the patch has been loaded. I have one WinXP machine which had the problem, and I have another two WinXP machines which did NOT have the problem. I have also verified with other people running Win2K that this problem exists on some of their patched machines too. It may also occur on other versions of Windows, but I have not yet verified this.
I will be keeping an eye out for information from Microsoft about this problem – hopefully they will release a fix for this fix.
I only discovered this problem last night after noticing that another task hadn’t run. It turns out it hadn’t been running all week, and neither had my backups of this blog or any of my other sites and forums, which are run from my machine using task scheduler ! That could have been catastrophic !!