How to Unblock a Sender in Outlook Email

To undo a block in Outlook, open the blocked-senders list for your version of Outlook, select the address or domain, and remove it. In Outlook.com and new Outlook for Windows, go to Settings > Mail > Junk email; in classic Outlook for Windows, open Home > Junk > Junk E-mail Options > Blocked Senders.

What blocking a sender does in Outlook

Blocking tells Outlook to treat mail from a particular email address—or, if you blocked one, an entire domain—as unwanted. Depending on the Outlook app and the account behind it, messages may be sent to the Junk Email folder or otherwise handled as junk. Blocking is different from unsubscribing: it does not ask the sender to stop sending mail, and it does not necessarily remove you from a mailing list.

It is also different from marking a message as junk. A blocked-senders list is an explicit list you or an administrator can edit; junk filtering can also classify a message based on its content, reputation, or organizational policy. Removing an address from the list reverses that particular block, but does not guarantee that every future message from it will land in the Inbox.

Unblock a sender in Outlook.com or new Outlook

These instructions apply to Outlook.com in a browser and generally to the new Outlook app for Windows. The appearance of the settings panel can vary slightly as Microsoft updates Outlook, but the setting is under Mail and Junk email.

Select the Settings gear in the upper-right corner.
Choose Mail, then Junk email.
Find the Blocked senders and domains list. Locate the exact email address or domain you want to allow again.
Select the remove or delete control next to that entry. If the interface offers checkboxes, select the entry first and then choose Remove.
Save or confirm if Outlook presents a save button, then close Settings.

For example, if the list contains alex@example.com, remove that address rather than adding a new contact and assuming the block has disappeared. If the entry is example.com, it is a domain-level block and may affect many addresses ending in that domain. Review the text carefully before removing it.

Unblock a sender in classic Outlook for Windows

Classic Outlook for Microsoft 365 has a separate desktop interface. In the Windows app, open the Home tab and choose Junk > Junk E-mail Options. In the dialog box, open the Blocked Senders tab, select the address or domain, and choose Remove. Select OK to close the dialog and apply the change.

If you do not see Junk on the Home ribbon, check the Delete group or the ribbon’s overflow menu; the layout can change with window size and customization. Make sure you are using classic Outlook rather than the newer Outlook app, because their settings screens are not the same. If Outlook is connected to a work or school mailbox, your organization may also enforce server-side filtering that you cannot change from this personal blocked-senders list.

Outlook for Mac and mobile apps

Outlook for Mac has more than one interface, so the path depends on whether you use new Outlook or legacy Outlook. In new Outlook for Mac, open Settings and look under Mail > Junk Email for the blocked senders list. In legacy Outlook for Mac, the setting is commonly available through Tools > Junk Email Preferences, where you can select the blocked address and remove it. If those labels are not present in your release, use Outlook.com in a browser with the same mailbox; its Junk email settings provide a straightforward way to inspect the list.

Outlook for iOS and Android changes its menus over time, and the full blocked list may not be exposed in the same place in every account or app release. Check the app’s settings for junk or blocked senders. If you cannot find the entry or remove it, sign in to the account in a web browser and edit the list there. For a work account, ask your Microsoft 365 administrator if the sender is blocked by an organization-wide policy.

What happens after you remove the address

Unblocking affects how Outlook handles mail going forward; it usually does not move earlier messages back to the Inbox. Look in Junk Email for messages that arrived while the sender was blocked. If you find a legitimate message, select it and use the option to mark it as not junk or move it to the Inbox. In some Outlook versions, marking a message as not junk may also offer a choice to trust the sender, but check the prompt rather than assuming that moving a message changes every filtering list.

Also check Deleted Items if you may have deleted the message yourself. A message that is no longer in either folder may have been removed by a retention rule, mailbox cleanup, a security system, or an administrator. Unblocking cannot restore mail that Outlook has already permanently deleted, nor can it recall messages that the sender never successfully delivered.

After removing the block, ask the sender to send a new test message. This is a useful way to distinguish an old message that remains in Junk from a new delivery problem. If the new message arrives in Junk, mark it as not junk and investigate other rules or filtering controls.

If the sender is still blocked or mail still goes to Junk

First verify that you edited the list for the correct mailbox. People often have a personal Outlook.com account and a separate work account open at once, or several accounts added to one app. Check the account name or email address shown in Outlook, then inspect that mailbox’s blocked list.

Next, check for another setting that could produce the same result. A rule may move or delete messages based on the sender, subject, or other conditions. In Outlook.com or new Outlook, review Settings > Mail > Rules. In classic Outlook for Windows, review Home > Rules > Manage Rules & Alerts. You can also check whether the sender’s address has been added to a blocked list in another client or through your organization’s email security service.

Search the Blocked senders and domains list for both the exact address and its domain.
Check Junk Email, Deleted Items, and any folder targeted by a rule.
Confirm that the sender is using the same address you unblocked; companies sometimes send from multiple addresses or domains.
For a work or school mailbox, ask the administrator whether a tenant-level block, quarantine, or mail-flow rule is involved.

Some messages are sent to Junk because their authentication, links, or sending reputation trigger filtering, even when the sender is not on your personal blocked list. Conversely, a company security policy may block a sender for everyone in the organization. Removing your own entry will not override that policy. If a message is in quarantine, use the release or review process provided by your organization rather than repeatedly changing the Outlook list.

Address blocks, domain blocks, and safer alternatives

An address block affects mail from one exact address, such as alex@example.com. A domain block affects addresses from a broader domain, such as example.com. Domain blocks can be useful for persistent unwanted mail from many addresses at the same organization, but they can also catch legitimate messages from other people at that domain. If only one correspondent should be allowed again, remove the specific address when possible and avoid adding a broad domain block.

If Outlook keeps misclassifying one trusted sender, adding that address to Safe senders can be an alternative to repeatedly moving messages from Junk. In Outlook.com or new Outlook, look under Settings > Mail > Junk email for the Safe senders and domains list. Add only an address or domain you trust. Safe-sender settings are not a promise that every message will bypass every security control: organization policies and other protections can still affect delivery.

If the mail is a newsletter you no longer want, use its legitimate unsubscribe link or the sender’s account preferences instead of blocking it, provided you trust the message and the link. For suspicious or unsolicited mail, do not click links just to unsubscribe; use Outlook’s report-junk controls. These choices address different problems: unblocking allows a sender again, safe-sender settings can help trusted mail avoid ordinary junk classification, and unsubscribing requests fewer messages.

Frequently Asked Questions

Will unblocking a sender restore emails already in Junk?
No. Removing the block normally affects future handling, not messages already filed away. Check Junk Email and move legitimate messages to the Inbox or mark them as not junk.

Does unblocking guarantee that the sender’s next email reaches my Inbox?
No. A rule, junk filter, quarantine, delivery failure, or organization-level policy may still affect it. Check the relevant folders and settings, and ask the sender to send a new message.

Can I unblock someone in Outlook on my phone?
Possibly, depending on the app version and account. Look in the app’s settings for junk or blocked senders. If the list is unavailable, edit it through Outlook.com in a browser or ask your work or school administrator.

Why can’t I remove an address from the blocked list?
You may be viewing a different mailbox, using a different Outlook interface, or dealing with a list controlled by your organization. Confirm the account and try the web settings; contact your administrator if the block is centrally managed.

Should I block an address or its whole domain?
Block the exact address when the problem is limited to one sender. Block a domain only when you intend to affect mail from all addresses at that domain, because that can also divert legitimate messages.

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