avastsvc.exe: the very first dependency, APPHELP.DLL, is missing.
"Error opening file. The system can not find the file specified. (2)"
Same problem with aavm4h.dll and several other DLL files. In each case, APPHELP.DLL is the only library that is missing.
But check this out:
http://www.dependencywalker.com/faq.html
Q: Dependency Walker says I'm missing APPHELP.DLL. Where can I get it from?
A: APPHELP.DLL is used by Windows XP's application compatibility feature. It is a Windows XP/2003/Vista/7/+ only DLL. If you see this warning, you most likely installed Internet Explorer 6.0 on your pre- Windows XP computer (Windows 95/98/ME/2000). Internet Explorer 6.0 installs a new SHWAPI.DLL that has a delay-load dependency on APPHELP.DLL. This is normal as SHWAPI.DLL does not expect to find APPHELP.DLL on versions of Windows prior to Windows XP. This warning can be ignored. You do not need (or want) APPHELP.DLL on Windows 95/98/ME/2000.
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I still have to check the other Win2k computer, but I know this one is definitely running IE 6.
So: shot in the dark here, but is it possible that the avast! installer detected the presence of IE 6, and as a result, automatically assumed that APPHELP.DLL existed, and installed the wrong binaries?
I have another Win2k computer that is running avast! with no issues - but I don't have access to it at the moment, and can't check which version of IE it is running.