Here some info on SRSReset for SCOM reporting.
http://blogs.technet.com/mgoedtel/archive/2007/07/09/operations-manager-reporting-resolving-those-errors.aspxhttp://www.aquilaweb.com/blog/index.php?itemid=32Uninstall SCOm reporting - Reset srs and reinstall is in my opinion the best way to go, once you start having trouble with reporting it almost never goes away easy.
Your costumer reports will be gone after that, just to keep in mind.
Regards,
Walter