Have you tried mrsexlovers advice He advised in another topic ....I have the same thing happening to me, as i use McAfee and normally have my Realtime Scanning on, that is causing the problem, so when ever i get a message upgrade failed i close down Achat again.Then i got to McAfee turn the Realtime scanning off and not closing that screen i start up Achat. Now it upgrades just fine and as soon as the update is done and the program starts i turn my Realtime Scanning back on.Then everything is just fine and all works.I hope this helps you