Just tried and it works with my Google-Account.
Which MyPhoneExplorer do you use ? Update to v1.7.2 if you have a previous version
Did you check username and password ?
Do you use any Routers, Proxies or Firewalls which could block the connection ?
Yes - this is strange. Please start MyPhoneExplorer in Debugmode (Start-Run-myphoneexplorer debug-OK) and after the errormessage please send me the logfile via email (do not post it here cause there are maybe private data in it)