How to Undo Block Sender in Outlook and Unblock Emails

To undo Block Sender in Outlook, remove the address or domain from your blocked senders list: in Outlook on the web or new Outlook, open Settings > Mail > Junk email; in classic Outlook for Windows, open Home > Junk > Junk E-mail Options > Blocked Senders. Select the entry and remove it, then save or confirm if prompted. You will need access to the Outlook account where the block was added.

What You’ll Need

Access to the correct Outlook account. If you have more than one Microsoft, work, or school account, make sure you are signed in to the one that received the blocked message.
The sender’s email address, or the domain you want to unblock. If you do not know it, look at an old message or ask the sender to confirm their full address.
A current browser or Outlook app. Menu labels and icons can vary slightly by version, but the blocked list is managed in Outlook’s junk email settings.

Step-by-Step

Choose the Outlook version you use. Outlook on the web, new Outlook for Windows, and classic Outlook for Windows have different routes to the blocked list. The web and new Outlook settings are similar. If you use classic Outlook, use its Junk E-mail Options dialog instead. Unblocking a sender in Outlook does not require contacting the sender or changing their email account.
Open the blocked list in Outlook on the web or new Outlook. Select the gear icon for Settings, then choose Mail > Junk email. In the section called Blocked senders and domains, look for the address or domain you want to allow again. In a work or school account, open Outlook in a browser or the app associated with that account; the setting must be changed in the account that received the mail.
Remove the matching entry. Find the exact address or domain in the list, then select its remove or trash icon. If the list is long, scan it carefully rather than deleting entries you do not recognize. An address such as name@example.com blocks that sender, while a domain such as example.com can affect mail from multiple addresses at that domain.
Save the change if Outlook asks. Some versions apply the removal immediately; others display a Save button at the bottom of the settings pane. Select it if it appears, then close Settings. If Outlook offers a confirmation prompt, confirm that you want to remove the entry from the blocked list.
Open classic Outlook for Windows if that is your app. In the main Outlook window, select the Home tab, then Junk > Junk E-mail Options. In the dialog box, open the Blocked Senders tab. This list is separate from the settings pane used by new Outlook, so be sure you are following the route for the Outlook app you actually use.
Remove the sender in classic Outlook. Select the address or domain in the Blocked Senders list and choose Remove. If you see more than one entry related to the sender, remove only the ones you intend to unblock. Select Apply, then OK, if those buttons are available, to save the change and close the dialog.
Check the result with a new message. Ask the sender to send a fresh email, or wait for the next message. Check your Inbox and Junk Email folder. Removing an address from the blocked list does not move earlier messages back into the Inbox, restore deleted mail, or guarantee that a message will arrive if another rule or mail filter affects it.

Outlook for Mac: Open Outlook’s settings from the Outlook menu, then look for Junk Email or Mail > Junk Email, depending on your version. Open the blocked senders list, select the entry, and remove it. Close Settings or save if prompted. Microsoft changes the Mac settings layout from time to time, so if those labels do not appear, use Outlook’s Settings search for “Junk Email” or check the app’s help for your installed version.

Common Mistakes

Changing the wrong account. A block belongs to an account, not necessarily to every account shown in Outlook. If you have a personal Outlook.com mailbox and a work mailbox in the same app, verify the account before editing its list.
Removing only one of several entries. You may have blocked a sender’s exact address and their whole domain separately. Removing the address will not undo a domain-level block that still matches their mail. Review the list for both forms, but remove only entries you trust.
Expecting old mail to return automatically. Unblocking changes how future incoming mail is handled. It does not recover a message that was deleted, nor does it necessarily move an existing message from Junk Email to the Inbox. Search all mail folders for older messages.
Confusing a block with a rule or a subscription preference. A message may still be moved, deleted, or redirected by an inbox rule, a sweep setting, a mail-flow policy, or a sender’s mailing-list preferences. Removing a blocked-list entry will not cancel those other actions.
Blocking a whole domain by mistake. A domain entry can block more than one sender. If you only want to receive mail from one person at a company, remove or adjust the broad entry carefully rather than assuming it affects just that one address.

Tips

Use the full address. Compare the blocked entry with the address in the From field of a known message. Display names can be misleading, and a sender may use more than one address.
Check both blocked senders and safe senders. If a trusted sender’s messages keep going to Junk Email after you remove the block, add the exact address to Safe senders and domains in the same Junk email settings page, if that option is available. Safe-listing is useful but does not override every organizational filter.
Check Junk Email before making another change. If the next message arrives there, mark it as not junk or move it to the Inbox. That can help Outlook learn your preference, although it does not replace removing the sender from the blocked list.
Keep a record of broad blocks. If you manage a long list, note why a domain was blocked before removing it. This is especially useful for shared or work mailboxes, where a domain-level choice can affect messages from many people.
Allow time for work-account changes to take effect. Some Microsoft 365 organizations apply additional filtering outside your personal Outlook settings. If you have removed the entry but mail is still blocked, an administrator may need to check the organization’s quarantine or mail-flow policies.

Troubleshooting

The sender is not listed. Confirm that you are signed in to the mailbox where the block was created, and check whether you are in new Outlook, classic Outlook, or Outlook on the web. Search the list for the sender’s full address and domain separately. If neither is present, the message may be handled by a rule, junk filter, another account, or a work administrator’s policy rather than the blocked senders list.

The message still goes to Junk Email. First verify that the blocked entry was removed and saved. Then open Junk Email and check the message’s details. If it is there, mark it as not junk or move it to the Inbox, and consider adding the address to Safe senders. Also review Settings > Mail > Rules in Outlook on the web or new Outlook, or the Rules option in classic Outlook, for a rule that moves messages from that sender. In a managed work or school mailbox, ask your IT administrator whether a policy or quarantine is involved.

You cannot find Junk E-mail Options or the settings page. You may be using a different Outlook version than you think. Classic Outlook for Windows has a ribbon and the Junk E-mail Options dialog; new Outlook and the web version use the gear icon and Mail settings. If your organization has customized Outlook, some settings can be hidden or managed centrally. Updating the app or opening Outlook on the web can help you identify which settings are available for the account.

You removed the block but old messages are missing. Search Outlook for the sender’s address, including in Junk Email, Deleted Items, Archive, and any custom folders. If the message was permanently deleted or expired under a retention policy, unblocking will not restore it. Ask the sender to resend it if it cannot be found.

The blocked list will not save or the option is unavailable. Refresh Outlook, reopen Settings, and try again. In classic Outlook, close and reopen the Junk E-mail Options dialog, then use Apply and OK. If the list is controlled by your organization or you lack permission to change it, contact your Microsoft 365 administrator rather than repeatedly changing unrelated settings.

Frequently Asked Questions

Does unblocking someone notify them?
No. Outlook does not send the person a notification when you remove their address from your blocked senders list. They will only know if you tell them or reply to a later message.

Will unblocking restore emails they sent while blocked?
No. Removing the block affects future handling. Search Junk Email and other folders for older messages, but a deleted or expired email may not be recoverable. The sender can resend anything you still need.

Can I unblock a sender in Outlook on my phone?
Outlook’s mobile app does not always expose the full blocked senders list, and available settings can vary by app version and account. If you cannot find the list in the app’s settings, open Outlook on the web in a browser and use Settings > Mail > Junk email.

What is the difference between removing a block and adding a safe sender?
Removing a block stops that entry from explicitly blocking the address or domain. Adding a safe sender tells Outlook to treat the listed address or domain as trusted when possible. If messages still go to Junk after unblocking, safe-listing the exact address may help, but organization policies can still take precedence.

Does blocking a domain block every address from that company?
A domain entry can affect addresses that use that domain, not just one person. For example, blocking example.com can affect multiple senders whose addresses end in @example.com. Remove a domain entry only if you want to allow mail from that domain again.

Why does an unblocked sender’s email still not arrive?
The sender may be using another address, or a rule, junk filter, delivery failure, quarantine, or organization policy may be involved. Confirm the exact From address, check Junk Email and Deleted Items, review rules, and ask a work or school administrator to check quarantine if needed.

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