avast memory shutdown problem

Once in a while when I shutdown my pc avast’s AshDisp will bring up a message that says memory problem has occurred with this application. It gives a long reference number and this all ususally happens right before the [ Windows is shutting down now ] message. Has anyone else had this problem and is it fixable?

This problem should be solved if you install the latest update. (4.6.603)

why? Was all this a problem for others too?

Sometimes it would happen to me.