Troubleshooting IMAP authentication issues

When trying to signup / authenticate / connect an inbox for an IMAP account using the IMAP protocol and it returns an error, follow this troubleshooting guide.

Description

Most of the time the problem relates to:

• Wrong port number
• Server does not have a valid SSL/TLS connection.

Resolution

1. Try the IMAP connectivity test via https://testconnectivity.microsoft.com/tests/O365Imap/input

This is the host.name.com that typically has the port number 993 attached

1. • Ensure Authentication is set to Basic
   • Verify the result of your test and confirm it passes. If it shows an error please reach out to your email admin.
     
     

     This only tests the IMAP side, not the SMTP side, nor does it test the SSL certificates
     Confirmed: We now know the username / password and port 993 are correct.

2. Run the SMTP test via https://www.gmass.co/smtp-test

This is the host.name.com that typically has the port 465 / 587 associated with it.

• • • Choose SSL under security.
    • Verify the result of your test and confirm it passes. If it shows an error please reach out to your email admin.

Please ensure both these tests pass in order to connect an IMAP account with Nylas.

Updated May 16, 2023 15:42