Sign-in fails

  1. Check that webmail works and the account is accessible.
  2. Check the full address and the required app password.
  3. Confirm IMAP access is permitted and the administrator has not blocked it.
  4. If your provider requires Google or Microsoft sign-in, check whether that option is available in the account setup window. If it is missing, ask the provider or administrator whether an app password is allowed.

No new messages appear

Check internet access, account and folder selection, then remove list filters. Look in webmail, including Spam. Verify the IMAP hostname, port and TLS mode against the provider’s documentation. Do not turn off certificate checks to make a connection work.

Receiving works but sending fails

Check the SMTP hostname, port, TLS and authentication separately. The sender address should belong to this account. After an interrupted send, check Sent first: the server may already have accepted it. Then restore the message from the outbox; interrupted sends are not blindly resumed after a crash.

Ask for help without sharing secrets

Include the Postosha version, provider, failing step and a redacted error. Do not send passwords, tokens, account export files or message content. The support contact is in the footer.