Okay...

Let's try something different. Where is/are your copies of riched20.dll? Mine are:

riched20.dll - c:\winnt\$NtServicePackUninstall$ - 422KB - 7/22/2002
riched20.dll - c:\winnt\ServicePackFiles\i386 - 422KB - 6/19/2003
riched20.dll - c:\winnt\system32 - 422KB - 6/19/2003
riched32.dll - c:\winnt\system32 - 4KB - 12/7/1999
riched32.dll - c:\winnt\system32\dllcache - 4KB - 12/7/1999

Actually, you should not have had to run the installs individually. That implies that something big and bad is happening.