Error Code 1603 when trying to install TFS 2010 SP 1
TFS 2010 SP 1 fails with:
Product: Microsoft Team Foundation Server 2010 - ENU - Update 'KB2182621' could not be installed. Error code 1603.
In my case the log file indicated that permissions to the Master database were missing. I made sure the setup user got sysadmin priviledges for the time of the SP install and it went through very smoothly.