It may not be an error - if the product is running latest dats (if using McAfee Repositories) or the latest dats available in ePO (if ePO managed) then it could be correct.
McAfee release normally 1 set of dats per day - usually sometime like 4-5pm UK time - so if a dat update runs at e.g 6pm (UK) and new dats are applied - if the update task again runs at 8pm(UK) in normal circumstances McAfee will not have released new dats so it would be correct as there is actually no new update found.
Also don't forget most McAfee windows based products like msme, vse etc use mcafee agent for updating - this is a common updater so if VSE (or another product) requests an update this will also check which other products are installed and update those as well ... msme update request would mean the agent checks msme and other products installed if reuire update.
So default VSE update task is 5PM - so if dats already available this VSE request will update MSME also .... any msme task run after this may not find new dats until next dat release from McAfee
