Norton Internet Security Free Trial Not Scanning

Please excuse me if this is posted in the wrong place.  This is my first post.  Anyway I bought a new Windows 8 PC with Norton Internet Security Free Trial installed.  Everything seems to work fine but a couple of days ago I clicked on computer scan and nothing happened.  It didn't matter if I clicked on Custom, Quick or Full Scan.  The only scan which worked was Reputation Scan.  I went on the online support and was advised to re-install.  This I did and the scan options were apparantly fixed.  I did a quick scan and all seemed well.  Until today I clicked on scans just to check that all was still ok and lo and behold I am back to the same problem.  Anyone got a lasting answer to my problem?

 

Read another post with a similar problem and the only solution was to restart the PC.   Surely this is a problem that Norton should be able to sort out without this restart idiosy!