"Page was not found" or: What is going on out there?

Update: JTA is inaccessible for me again. I tried private browsing with no effect. So VPN is the only way to bypass the issue.
 
Could be a problem with your DNS server or cache. Do you have any local software that blocks ads by IP address, a local DNS server or modified hosts file, etc? Some configuration problem with one of those things could have resulted in a bad address being assigned to that particular web page. Going through a VPN is likely resulting in the IP lookup being done at some point that is not local to you and doesn't use any of your settings.

Mike