Hiya @hoptown1963, I am really sorry for the issues being experienced with mail on your client.
Can you advise which client you are using? If not already done so I would advise just to go into the server settings and check all other details are correct. Has there been any kind of update to your mail client recently?
If you are still unable to get this working, you may need to look at removing the account and then re-adding it though as you are using POP3, please make sure that you have any important emails backed up as this could wipe them depending on your settings.
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