We have seen issues like these be caused for a few reasons...
One is resolved by applying the latest Patch for ePO 4.0.
But the others were due to issues with the Database. These type issues will typically require that you submit your DB to McAfee support and have them attempt to reproduce the issue, and possibly resolve the back end SQL issues.
Try installing patch 5 first (if your not already on that), and if that doesn't work, I would open a ticket with McAfee Tier I Support.