Cannot send e-mails

Question

My outlook e-mail quite working due to exceeding my storage limit. I fixed that by getting rid of a bunch of old e-mails. Now I can receive e-mails but I cannot send any e-mails. I keep getting a system error message.

Answer 1

Hi,

If you are sending an email, what exact error message are you getting?

Are you on macOS or Windows? Are you using the Outlook app (new or classic) or the web version?

In the meantime, try the following:

Please try using a different internet connection, then open an InPrivate window (Ctrl + Shift + N) in your browser and try logging in to your account using the link below:

https://account.microsoft.com/

Can you send emails there?

Also, check if your storage space has been updated by visiting: https://outlook.live.com/ Go to Settings > Accounts > Storage. Expand both the Microsoft Storage and Cloud Storage sections.

Answer 2

Follow these steps in order, testing sending after each step:

1. Confirm storage is really under the limit
   Even if old messages were deleted, the mailbox or Microsoft cloud storage may still be over quota until items are emptied from Deleted/Trash.
   • In Outlook.com, check storage usage (Email storage and Microsoft storage). If either is full, permanently delete items from Deleted Items/Trash and large folders until usage drops below the limit.
2. Check for large or stuck messages
   Large attachments can block sending.
   • Look in Drafts and Sent (and any Outbox folder if visible) for messages with large attachments (over ~20 MB).
   • Open any stuck message, remove large attachments or replace them with a link (for example, via OneDrive), then send again.
     For more details on attachment limits and alternatives, see the guidance in the Outlook sending/troubleshooting article and the Exchange Online limits and “Reduce attachment size to send large files with Outlook” sections referenced there.
3. Verify Outlook is online and connected
   If using classic Outlook with Outlook.com:
   • Look at the status bar at the bottom. If it shows Disconnected, Working Offline, or Trying to connect…, Outlook cannot reach the server.
   • On the Send/Receive tab, select Work Offline once to toggle back online, then try Send/Receive again.
   • Confirm the internet connection by opening a browser and visiting a site such as http://www.microsoft.com or http://www.bing.com. If those do not load, fix the network issue first.
4. Check for OneDrive/Microsoft storage issues
   If Microsoft cloud storage (OneDrive + other services) is full, sending and receiving email can be blocked even if email storage looks fine.
   • Use the mailbox storage link in the storage notification or account portal to see what is using Microsoft storage and free space there (delete or move files, then empty recycle bin).
   • After freeing space, wait a short time and try sending again.
5. If using Outlook for Mac with Outlook.com
   • Ensure Microsoft cloud storage is not full using the mailbox storage page.
   • Confirm Outlook is not set to Work Offline (Outlook menu > Work Offline unchecked).
   • If using POP/IMAP with Outlook.com, verify SMTP authentication is enabled in Tools > Accounts > Outgoing server > More Options and that the correct credentials are entered.
6. If the problem persists
   • Note the exact system error message text and code.
   • Use the in-product support option: in Outlook for Mac, select Help > Contact Support; in Outlook.com, use the help/support option in the web interface. Provide the error text and confirm that storage is now under quota.

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References:

• I can't send or receive messages in Outlook
• My email message doesn't send
• I can't send or receive messages with Outlook for Mac
• Microsoft storage limit exceeded - Microsoft Q&A
• my outlook email is not delivered - Microsoft Q&A
• storage exceeded in outlook after purchasing MS 365 subscription - Microsoft Q&A
• How to increase attachment size limitation - Microsoft Q&A