have you restarted the computer and the modem since it began?
this is for Lacerte, but those are the first 2 things to try
https://proconnect.intuit.com/community/data-security/help/internet-error-xxxxx-unable-to-establish-...
♪♫•*¨*•.¸¸♥Lisa♥¸¸.•*¨*•♫♪
