Yahoo Mail Not Sending or Receiving Emails
Quick answer: Check the Outbox for a stuck attachment if mail won't send, check Spam first if mail isn't arriving, and check your storage quota if it's affecting both directions at once.
Can't sign in at all? That's a separate problem — see our Yahoo Mail login guide instead. This one's for once you're already in, and mail still isn't moving right.
1. Emails stuck in the Outbox or "sending" forever
- Check for an oversized attachment on the stuck message first — in my experience, this is the cause more often than everything else combined. Remove it, or send it as a link to cloud storage instead.
- Sending through a third-party app? Confirm the outgoing settings are current:
smtp.mail.yahoo.com, port 465 or 587, SSL/TLS with authentication required. - If two-step verification is on, make sure that app is using an app password, not your normal Yahoo one — see our login guide for how to generate one.
2. Emails not arriving
- Spam first. Yahoo's filtering leans aggressive, and this alone resolves most "missing email" reports I hear about.
- Settings → More Settings → Filters — check for an old rule silently moving, deleting, or forwarding incoming mail.
- Settings → More Settings → Mailboxes — check for an old forwarding address you forgot was still active.
3. "Mailbox full" or storage warnings
A full mailbox can block both directions, not just one.
- Search for large attachments and clear out the biggest offenders.
- Empty Trash and Spam — deleted mail still counts against your quota until those get emptied too.
4. Works on the website but not in an app (or vice versa)
Sign in to Yahoo Mail directly on the web to see whether the problem shows up there too.
- Broken on the website too — the problem's with the account itself, not any one app.
- Website's fine, one app isn't — that app needs attention specifically: outdated SMTP/IMAP settings, an expired app password, or it just needs updating.
5. Intermittent — works sometimes, not others
This pattern usually points to your connection rather than the account. Try the same thing on a different network — mobile data instead of Wi-Fi — before assuming anything's actually wrong with Yahoo.
If a sender got a bounce-back message trying to reach you, ask for the exact wording. "Mailbox full," "address not found," and "message rejected" each point to a different fix rather than leaving you to guess.