IP address blocked for incoming mail?

As of yesterday morning I am unable to download mail through Outlook. I get a “Failed to connect to server” error when trying to connect to pop3.comcast.net or mail.comcast.net. I am, however, able to connect to smtp.comcast.net and send mail.

If I log on to my VPN software, which changes my IP address, I am able to download mail. When I go back to my Comcast supplied IP it fails once again. This is repeatable.

Connecting to the incoming mail server fails with my Comcast IP but succeeds with a VPN supplied IP. It looks like my Comcast IP is being blocked.

One and a half hours on the phone with support got nowhere. First there was a known problem being worked on, then there was never a problem. Yet still no email access.

Nothing was changed, all settings have been checked, all equipment rebooted. Problem exists on all PCs with all email accounts and all client software. Only a change in IP allows for server connection.