230 votesJohn S Harrington commented
The following may solve some of the issues some of you may be having.
Set airmail to use imap or pop manually, some authentication issues may arise if you attempt to use you actual login/password.
- Remove the old account you are trying to 'fix' and restart airmail.
- On airmail click preferences and "+" and select imap or pop.
- Fill out your email address.
- Log in to your email client on the web then go to the options. Look for imap/pop options.
You will see some domains that your provider has listed for pop, imap, and smtp.
- Copy the appropriate link (depends if you selected pop or imap on airmail)and place them in the appropriate fields in airmail. Outgoing will always be the smtp domain
- Go to your email provider account and generate an app password.Copy and paste that password into the password field on in airmail. Click save.
The authentication process will start and may take a minute or two. Once it's done you can start send emails.
Once you are done send a test email to yourself or a friend just to be sure.
Note* This was tested on outlook.