Why did my downloaded emails disappear when I changed email settings - and can I get them back?

HI Brainstrust -

I recently changed my domain name settings (DNS A records) and wasn't expecting it to change my email (MX records were not changed). But it did. Have now configured reconfigured the email DNS so that they come to my computer once again, but I seem to have lost all my previously downloaded emails.

I'm hoping they are recoverable... I can't find them on the server, which is not a problem as long as they are still on my computer somewhere.

More info, I set up the email to be IMAP not POP... could that be the issue?

Grateful for any help!