Hi, Thanks for your help. PFA the svcsetup.log file. I overlooked the log file and was thinking it is not there ******************************************************************************************************************** 12.937: 2012/05/02 14:10:56.765 (local) 12.937: D:\Win2k3 SP2\sp2\i386\update\update.exe (version 6.3.4.1) 12.937: Service Pack started with following command line: 12.937: In Function GetBuildType, line 1170, RegQueryValueEx failed with error 0x2 13.015: DoInstallation:CreateProgressDialog failed 13.078: UnRegisterSpuninstForRecovery, failed to delete SpRecoverCmdLine value, error 0x2 13.078: DoInstallation: Failed to unregistering spuninst.exe for recovery. 13.078: Service Pack 2 Setup canceled. 15.469: Message displayed to the user: Service Pack 2 Setup canceled. 15.469: User Input: OK 15.469: Update.exe extended error code = 0xf00d 15.469: Update.exe return code was masked to 0x643 for MSI custom action compliance. ********************************************************************************************************************* I tried to install in safe mode but the setup exit with error "Cannot find windows class" Any help will be greatly appreciated