On one SCCM site (Windows 2008 R2 and SCCM2007) WSUS core services failed because "MS DTC" service was not able to start.
Read more –> http://support.microsoft.com/kb/916926
This is how I got the site back online:
1. First I re-run WSUS installation so files were unpacked to C:\<folder>
2. Copy SSEE_10.msi to temp folder
3. Cancel WSUS setup (temp files are removed)
4. Open Admin CMD.exe and run this repair string from msi file folder:
Msiexec /i SSEE_10.msi CALLERID=OCSetup.exe REINSTALL=ALL REINSTALLMODE=omus /l*v c:\my_logfile.log
5. I removed and reinstallaed SUP service on the WSUS server.
6. After reboot the MS DTC started and SUP was back online!