Not sure what you are asking for, here. A quick search indicates that this error is to do with printers, not AV.
It's your printer you should be troubleshooting, I think. I don't see where Avast fits into the equation.
Please feel free to correct, though.
Regarding not losing your stuff, you need to copy your important files etc, in order of importance, to an external media.
DVD or external hard drive would be good.
Computer manufacturers' help lines often provide the fix that's easiest for the technicians (or in some cases, operators) on the other end of the help line, not what is necessarily best for the customer, particularly if the best fix might be complex.
I don't know what Dell is like in this regard; never bought one.