Found an interesting article today that may answer some of the AD schema issues that have crept into some hapless folks' ISA servers during installation into an AD structure. http://support.microsoft.com/support/kb/articles/Q303/0/77.ASP Bear in mind that this only affect Enterprise Edition and then only if you're installing in Enterprise mode (AD-integrated; you know, arrays). It appears that there is a rare bug in AD that sometimes creeps in when schema changes are made, corrupting the schema and making installation of schema-dependent (read: ISA) application problematic at best. According to this article, the bug was fixed in SP2, but since it's not 'officially' required for ISA installation, it doesn't get applied until the damage (if any) is already done. My take on it? If you're installing ISA Enterprise Edition in Enterprise Mode (AD-based), then apply W2K SP2 before you run the ISA schema wizard. If you're not using ISA Enterprise Edition or you're installing either version in standalone mode, install it anyway. If nothing else, it includes the post-SP1 fix that came on the ISA CD. -- Jim Harrison MCP(2K), A+, Network+, PCG