I'm somewhat new to linux / ubuntu and am trying to do a proof of concept.

I have installed a ubuntu server and installed postfix on it. The intent is to operate as a local (no internet) mail service.

I can successfully send and receive emails as long as I log onto the server.

I'm trying to use Thunderbird on a windows machine on the same local network to retrieve mail, but I am unsuccessful.

My searches have not come up with this exact configuration, and I'm afraid the example differences are causing me confusion.

My question is this: Where would I look for an answer? Ubuntu, postfix, or Thunderbird. I think I've tried them all.

Thank you for any direction.