That’s rather strange, many people use avast! on Vista without any problems.
What exactly does it mean “fails to load”? Bluescreen, any error messages?
Yes, avast! shouldn’t have any problems with the final version of Vista.
I don’t know how you reinstalled Vista or if the reinstallation deletes all the previous files - but just in case, please check the Windows\Minidump folder (if it’s there at all) - is there anything inside?
Well, honestly, I don’t know.
The latest build (4.7.942) doesn’t fully support early betaversions of Vista, but it should work correctly with the final version (and we didn’t receive any reports saying otherwise so far). The previous builds (<942) had some issues (though not so bad as you are describing), but the latest one should be OK.
Without more information (such as a dump file), we can hardly do anything about the problem (if there really is a problem in avast, of course).
It is also strange that the problem would appear even in safe mode… I don’t know if anything has changed in Vista, but avast! normally isn’t loaded in safe mode (in WinXP, for example) - so it can hardly affect the booting sequence anyhow… ???
So, avast! was the first thing you installed after Vista installation finished?
When you installed Avast did you download the setupengpro.exe file directely or did you just ran it because you already had the installer on your computer ?