If you know when the problem began, try a System Restore to a point in time BEFORE the problem began. Here's the procedure:
http://www.howtogeek.com/howto/windows-vista/using-windows-vista-system-restore/. Be sure to check the box to show more than 5 days of restore points. If the first attempt fails, then try an earlier point or two. NOTE: You will have to re-install
any software and updates you installed between now and the restore point, but you can use Windows Update for the updates.
You can also go to Start / Control Panel / Administrative Tools / Services and check to see if Task Scheduler is automatic and started. If it's stopped then click on it and start it (and make sure it's set on automatic).
If that doesn't work, check some of your system files:
Go to Start / All Programs / Accessories / Command prompt and right click on command prompt and click run as Administrator.
Type sfc /scannow and enter and let it run. It will scan and try to fix some of your system files. Hopefully it will complete with no corruption it could not repair (if there is such corrouption post back here or try to analyze it to find the problem file(s)
If that doesn't work, we'll need to do a system repair/upgrade using the genuine Windows Vista Installation Disk (one you own or one you can borrow from ANYONE). Here's the procedure:
http://www.vistax64.com/tutorials/88236-repair-install-vista.html along with the upgrade from an earlier version of Windows section of the following:
http://support.microsoft.com/kb/918884. Although this will not affect your data, settings, or programs, you should still backup your data before starting just to be on the safe
Hopefully one of these procedures will resolve your problem (probably the System Restore). If not, post back and we'll try something else. Post back in any case so we'll know how it turned out.
Lorien - One - MCSE/MCSA/Network+/A+
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