Sending, receiving, and organizing email in Outlook.com
Deleted mail does not free space immediately if it is still in Deleted Items. That folder continues to count against the mailbox quota until it is emptied.
Try this in Outlook.com:
- Open Settings > Account > Storage.
- Check which folders are using the most space.
- Use the cleanup options there to permanently delete items, including items older than 3, 6, or 12 months.
- Empty Deleted Items manually.
- Check Junk as well. Junk mail is automatically deleted after 10 days, but until then it can still be present.
- For individual messages, use Shift + Delete to permanently delete them instead of sending them to Deleted Items.
- Sign out, then sign back in and check whether the storage value updates.
Important:
- If storage was full, mail sent during that time is returned to the sender and must be resent after the mailbox is back under quota.
- If the problem is actually Microsoft Unified Storage is full, Outlook.com mail can still stop even when email storage itself is under limit. In that case, free up OneDrive/cloud storage or buy more storage.
- Free Outlook.com accounts have 15 GB of mailbox storage. Microsoft 365 consumer mailboxes are capped at 100 GB.
If storage still shows full after cleanup, there was a recent Outlook.com issue where storage stayed incorrect after space was cleared or extra storage was purchased. The documented workaround was to delete emails with attachments larger than 10 MB, then sign out and sign back in so the storage information refreshes.
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