According to Microsoft, the update causes a problem on Windows Server 2003 SP 2 with Service pack 2.
See the full Microsoft KB article explaining the problem:To resolve this problem, reinstall Service Pack 2 for Windows Server 2003 on the web server. This will bring all IIS 6.0 components up to the correct file versions, and will maintain the installation of the KB973917 update. Reinstalling the KB973917 update should not be necessary.
Another option is for users to uninstall the update to get Vault/Fortress working again.
See a discussion of this on our forum:
http://support.sourcegear.com/viewtopic ... 714#p53714