Avast is what was causing the problem for everybody. My printer is working perfectly now for both scanning and printing over wifi. I haven't trried re-installing Avast yet to see if any problems crop up.
Alright dude, I figured it out with help from another forum. Avast is causing the problem. You have to uninstall Avast - COMPLETELY uninstall every trace of it. I used iObit's Uninstall program which asks you to do a "Powerful Scan" after you uninsta...
I have the same problem with a differnt printer. I get the "An error occurred ..." message when trying to insall Quick Menu 2.2.2. I suspect it has something to do with Windows 8.1, which has caused no end of problems with my wifi adaptor.
