Mail.com Login and Sending Problems

Applies to: Mail.com web, Mail.com in third-party apps

Quick answer: Confirm you're using the exact domain you chose at signup, enable IMAP/POP under Settings before connecting a third-party app, and check for an oversized attachment if sending is stuck.

1. Can't sign in on the website

  1. Confirm you're using your full address, including the domain you picked at signup — Mail.com offers dozens of options, and mixing them up is a genuinely common mistake.
  2. Use "Forgot password" rather than guessing repeatedly, which can trigger a temporary lock.
  3. Clear cookies for mail.com, or try a private window if the login page itself seems stuck.

2. Third-party app (Outlook, Thunderbird, phone Mail app) won't connect

Mail.com needs IMAP/POP3 access explicitly enabled before any third-party app can connect — it's off by default on new accounts, which catches people out constantly.

  1. Sign in on the Mail.com website.
  2. Settings → POP3/IMAP → enable the protocol your app uses. IMAP's the better choice if you check mail from more than one device.
  3. Re-add the account in your app afterward — anything entered before you enabled this will keep failing even if it's otherwise correct.

3. Outgoing mail stuck or rejected

  1. Confirm outgoing settings match Mail.com's current documentation — server address and port shift occasionally, so don't trust old saved settings from years back.
  2. Check for an oversized attachment stuck in the outbox.

4. Account flagged or restricted

Free webmail providers sometimes apply sending limits on new or low-activity accounts as an anti-spam measure. If sending suddenly stops with no clear error, waiting a few hours before trying again is usually the fix, not a broken setting.

Managing several Mail.com domain aliases? Double-check which exact address you're troubleshooting — settings are sometimes per-alias, not account-wide.
Missing incoming mail specifically? See our guide on Mail.com not receiving emails.