Error 25004: vCenter server upgradation

Hi Friends
I am using a vCenter Server 5 with Windows Server 2008 R2 Enterprise.
I have local MS SQL 2008 R2 Standard version 10.50.2500.0 installed.
Now I want to upgrade from 5.0 to 5.0U1.when I start the Setup and it detects the installed version.
Right at the end of the process there occurs an error:
Error 25004.Setup failed to create the vCenter Server repository.
The vminst.log is attached.
Please help.
thanks
