If you do this, don't do a repair install. Do a fresh install of Vista 64. It will take more time, but it will be better in the long run. A repair install will borked any newer third-party software ...

An unstable or slow internet connection could also be why the Windows Update Error 0x800F0223 occurs. If the internet connection is slow, the Windows Update Service ...

The Event Viewer logs events that lead to errors. The event logs can help you understand what triggered or where exactly the issue is coming from so you can be apply the relevant troubleshooting steps ...

I've been running Symantec Corp AV ver 10.2 on 2 vista machines at home for awhile now, they've been fine. A few weeks ago windows security alerts started saying it can't find an AV program.