Storage Reduction Not Allowing Email Send

Hi, Evan Kaufman

This usually happens because Outlook has not fully updated the storage status yet, or because deleted mail is still sitting in folders that still count toward the quota. If Microsoft cloud storage is also full, Outlook.com can stay blocked even when the mailbox itself looks under the limit.

Here are some suggestions you can try:

Open Outlook on the web, go to Settings > General/Account > Storage, and check which part is still full. That page usually shows whether the problem is mailbox space, attachments, or overall Microsoft storage.

Empty Deleted Items and Junk, because those still count until they are manually cleared. If available, also open Recover items deleted from this folder and empty that too.

Sort mail by Size and remove the biggest messages or attachments first. It is also recommended that this be done in the web version, since that can update storage faster than the desktop app.

If the account still will not send after cleanup, sign out and back in, then give it a little time to resync. If it still stays stuck, use Help > Still need help? in Outlook.com support.

Thank you for your patience in reading, I hope this information has been helpful to you. 

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