cant unblock a email address

Try this in Outlook on the web or Outlook.com:

1. Go to Settings > Mail > Junk email.
2. In Blocked senders or Blocked senders and domains, select the email address or domain to remove, then select the remove icon.
3. Select Save.

If Save shows "couldn't save changes, something went wrong", use these workarounds:

1. Add the sender under Safe senders and domains first, then select Save.
2. Sign out of Outlook.com, close the browser, reopen it, sign in again, and try removing the blocked sender and saving again.
3. Check Junk Email and Deleted Items for messages from that sender, and mark them as Not Junk if found.

If the sender is still effectively blocked after removal, the sender may be using a different real address than the one shown. In that case, view the message headers, identify the real sender address, and remove or allow that address instead.

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