"Norton Power Eraser is already running" Error Code: 0x80045009,0

I tried to run NPE yesterday after running a Quick Scan -- I do this periodically just as an extra layer of safety.  I got a message that I needed to load updated version, which I did.  Once again tried running NPE and got to the part where NPE restarted my computer.  Computer restarted, and NPE appeared to be running normally, but then stopped.  I got the error code above, stating that NPE was already running and the Error Code 0x80045009,0.  I can find no way to clear this, and it has persisted through two additional restarts.  How do I get this to stop?