I've been trying to diagnose this for some time, and unfortunately Im still getting the dreaded anonymous logon issue when trying to connect to a sql db as a domain user. Steps taken: App Pool created with delegation service acct Site / Virtual dir running with Integrated Windows auth only Made sure site itself can use kerberos KB 215383 Service acct added to IIS_WPG group Service acct added to "act as part of operating system" under Local Security settings Service acct added to Log on as service under Local Security Settings HTTP SPN set for web address + service account (and FQDN) MSSQLSvc SPN set for sql box and domain acct sql is running as Trust for delegation turned on service acct, specified services, and sql service acct After all this, Im still getting the exact same error from when I started. Login failed for user 'NT AUTHORITY\ANONYMOUS LOGON'. This has advanced my balding by at least 5 years so far. I would greatly appreciate any additional tips on diagnosing or setting up.