My father uses Thunderbird as an email client, and he had been using the email address from his local phone company. He is moving and terminating his phone/internet account with that company. Will he still be able to see his existing messages as long as "keep messages in all folders for this account on this computer" is checked (under Synchronization and storage). I would also assume that he would need to uncheck the options under settings that tell Thunderbird to check for new messages. Other than that, would he need to do anything else to make sure he can still see his existing email messages?