Make sure your firewall isn't blocking Gaia. If that nor Flash needing updating is your cause, it could be your internet service provider.
Slower internet connection speeds can also cause this error. This likely occurs because Gaia's servers think that the connection wouldn't be able to handle the load placed upon it by Gaia. When I'm using satellite internet at my Mom's house, I'll always get that error for the same situations.
As for the email not working, that's an odd one. If you have not done so yet, try asking in the
Site Questions & Assistance Forums.
I hope I was able to help some!