Email · Repair guide

How to fix email not sending

10 fixes, easiest first4 min readUpdated November 2026

Quick fix

Make sure you are online, then open the Outbox, check the recipient's address and tap Send again. If it still fails, try sending from your provider's own website; if that works, update the password in your mail app or create the app password your provider requires.

What it means

When email won't send, the message usually sits in the Outbox or comes back with a delivery failure notice. Common reasons are no internet connection, a wrong recipient address, an attachment that is too large, a full mailbox or storage quota, or a mail app whose saved password no longer works. The bounce message, if you got one, normally says which.

Common causes

  • No internet connection, or the message is still waiting in the Outbox
  • A typo in the recipient's address
  • An attachment larger than your provider allows
  • Your mailbox or cloud storage is full
  • You hit a daily sending limit
  • Your mail app's saved password is wrong, or the account needs an app password
  • Security software or your network blocking outgoing mail

How to fix it

Work down the list. Each fix is safe to try before moving on to the next.

01Check your connection and the OutboxEasy

  1. Make sure you are online by opening any website.
  2. On iPhone or iPad, open Mail and go to the mailbox list. Tap Outbox. If there is no Outbox, your email was sent.
  3. If you see Undo Send in your inbox, the message hasn't gone yet; wait a few seconds.
  4. Tap the stuck email, check the recipient's address, and tap Send.
  5. In Gmail, also look in Sent and Drafts to see whether the message was sent or saved.

Why it helps: Mail waits in the Outbox when there is no connection or something about the message is wrong.

02Check if your email service is downEasy

  1. Gmail: check the Google Workspace Status Dashboard.
  2. iCloud Mail: check Apple's System Status page.
  3. Other providers: check your provider's official status or help page.
  4. If there is an outage, wait and try again later.

Why it helps: If the service itself has a problem, no setting on your device will fix it.

03Check the recipient's address and any bounce messageEasy

  1. Look in your inbox and spam folder for a failure notice. In Gmail it comes from Mail Delivery Subsystem with a subject like "Delivery Status Notification (Failure)".
  2. Read the reason given. A wrong address, a full mailbox on their side or spam filtering are common.
  3. Check the address for typos, extra spaces, quotation marks or a dot at the end.
  4. If it says the server had a temporary problem, try again later.

Why it helps: The bounce message usually names the exact reason the email didn't go through.

04Make large attachments smallerEasy

  1. Gmail personal accounts allow up to 25 MB per message; larger files are added as a Google Drive link automatically.
  2. Outlook.com can't send a message with an attachment larger than 25 MB.
  3. iCloud Mail: use Mail Drop for big files, compress the file, or use AirDrop if the person is nearby.
  4. Send several smaller emails, or share a link from your cloud storage instead.

Why it helps: Messages over the size limit are refused and stay unsent.

05Free up mailbox or cloud storageEasy

  1. Gmail: Gmail, Google Drive and Google Photos share one storage space. Check it on your Google One storage page.
  2. Outlook.com: open the mailbox storage page in Outlook settings to see what uses space. If your Microsoft cloud storage is full, you can't send or receive email.
  3. iCloud Mail: check whether your iCloud storage is full.
  4. Delete emails with large attachments and empty the trash or deleted items folder.

Why it helps: When storage is full, many providers stop you sending as well as receiving.

06If you sent a lot of email today, wait for the sending limit to resetEasy

  1. Gmail personal accounts can send up to 500 emails a day and to up to 500 recipients per message. If you see "You have reached a limit for sending mail", wait; Google says you can send again within 24 hours.
  2. Outlook.com: new accounts start with a low sending limit that rises over time.
  3. For a large group, Google suggests a Google Group so you send one email to the group address.
  4. Don't keep retrying in the meantime.

Why it helps: Providers block sending for a while after very high volume to stop spam.

07If sending fails only in a mail app, check its passwordMedium

  1. Sign in to your provider's website with the same email address and password. If you can send from the website, the problem is the app.
  2. If you changed your password recently, update it in the app.
  3. Yahoo: a mail app that doesn't show Yahoo's own sign-in page needs a Yahoo app password. Create one on your Yahoo Account Security page under External connections.
  4. iCloud Mail in apps not made by Apple: sign in to your Apple Account page on the web and, under Sign-In and Security, select App-Specific Passwords to create one. Two-factor authentication must be on.
  5. Yahoo: if you send from an extra address that hasn't been verified, you can get a 553 error; verify the address or send from your main one.
  6. Update the mail app to its latest version.

Why it helps: Mail apps stop sending as soon as the saved password is wrong or the provider needs a special app password.

08If you use Mail on a Mac with iCloud, check the outgoing accountMedium

  1. In Mail, choose Mail > Settings and click Accounts.
  2. Select your iCloud account and open the Server Settings tab.
  3. Set Outgoing Mail Account to your iCloud account.
  4. Try sending again from the Outbox.

Why it helps: Apple says a "could not be sent" alert in Mail often means the wrong outgoing account is selected.

09Check security software and your networkAdvanced

  1. Try sending on a different network, such as mobile data instead of Wi-Fi.
  2. If you use a VPN, turn it off and try again.
  3. Temporarily turn off antivirus or firewall software to test, then turn it back on straight away.
  4. If mail only sends with it off, ask the software maker how to allow your mail app.
  5. If you can receive but never send from a mail app, ask your internet provider whether it blocks outgoing mail (SMTP) to other email services.

Why it helps: Firewalls, VPNs and some networks block the connection mail apps use to send.

10Remove and re-add the email accountAdvancedBack up first

  1. Warning: removing an account can delete email already downloaded to this device. Copy the text of any unsent message you need first.
  2. On a computer, sign in to your provider's website and make sure your mail is there.
  3. On iPhone or iPad, go to Settings > Apps > Mail > Mail Accounts, tap the account, then tap Delete Account (or Sign Out, depending on your iOS version).
  4. Add the account again, using an app password if your provider requires one.

Why it helps: This replaces damaged connection settings with fresh ones.

Check it's fixed

  • The Outbox is empty and the message appears in Sent.
  • A test email to yourself or a friend arrives within a few minutes.
  • No failure notice arrives in the next few hours.

When to get help

If you can't send even from your provider's website, or bounce messages keep coming back, contact your email provider through its official help site. For a work or school account, contact your IT administrator.

Questions

Why can I receive email but not send it?

Common reasons are a wrong saved password or missing app password in your mail app, a network or internet provider blocking outgoing mail, or full storage. Try sending from your provider's website to narrow it down.

Why is my email stuck in the Outbox?

The device was offline, the attachment is too large, or the app can't sign in to send. Fix the cause, then open the Outbox and send it again.

How big an attachment can I send?

Gmail personal accounts allow 25 MB per message and Outlook.com can't send attachments over 25 MB. For bigger files, share a link from cloud storage or use iCloud Mail Drop.

What does "You have reached a limit for sending mail" mean?

Gmail has paused your sending after too many messages or recipients in a day. Google says you can send again within 24 hours, so wait before retrying.

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Still stuck?

Paste the exact message to find the closest fix, or search it on Google, Microsoft, Apple, Reddit and YouTube.

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