Hey guys-
Had the same issue last night- Called MS and worked with them for a bit over 3 hours- but got it solved.
First, yes- there is a problem with the installer... not sure what but as SP1 is updating your system, certain files get blasted...
To fix the problem without losing data due to a reinstall, you need to boot into a command line vai recovery disk or other means... You can go into recovery console with the XP disk or maybe even boot from a win98 floppy... not sure on that one-
Anyhow, you'll have to rename old files on the command line and then copy new ones back from another dir- once that is done, XP works as expected- well, it starts without error anyway.
BTW, the tech I worked with was awesome and indicated that this was such a recent issue that the notes he was working from to resolve this issue weren't on the knowledge base yet- but they would be soon.
Here are the steps...
XP / shlwapi.dll error after installing windows updates.
After installing service pack 1, and then installing some other updates (possibly
without rebooting) you get the error.
"Winlogon.exe. Entry Point Not Found The procedure entry point AssocIsDangerous
could not be found in the dynamic link library SHLWAPI.DLL."
<><><><><><><><><><><><><><><><><><><><><><><><><> <><><><><><><><><><><><><><>
*** Resolution ***
"Winlogon.exe. Entry Point Not Found The procedure entry point AssocIsDangerous
could not be found in the dynamic link library SHLWAPI.DLL."
You can only reboot after that.
1. Boot to Recovery Console.
2 . type the following commands
cd system32 [enter]
ren winlogon.exe winlogon.old
ren msgina.dll msgina.old
ren shell32.dll shell32.old
ren shlwapi.dll shlwapi.old
cd.. [enter]
cd servicepackfiles\i386 [enter]
copy MSGINA.DLL c:\windows\system32
copy SHELL32.DLL c:\windows\system32
copy WINLOGON.EXE c:\windows\system32
copy shlwapi.dll c:\windows\system32
if not there, expand from the cd
3 Type EXIT and hit enter
After I did the above, all was good. Hope this helps speed some of you along.
Best,
Patrick