How to Unblock a Sender in Outlook on Desktop and Web

To unblock a sender in Outlook, remove their email address or domain from your blocked-senders list, then check Junk Email and mark any legitimate message as not junk. In Outlook on the web or the new Outlook for Windows, go to Settings > Mail > Junk email; in classic Outlook for Windows, open Junk E-mail Options from the Junk menu. The exact screen varies by version, so use the matching steps below.

What You’ll Need

Access to the Outlook account where the sender was blocked. If you use several Microsoft accounts, make sure you are signed in to the right one.
The sender’s exact email address, or the blocked domain if the entire domain was added. A message from the sender is helpful but not essential.
A web browser or the Outlook app. You may need to use Outlook on the web or desktop to edit the blocked list if your mobile app does not show that setting.

Step-by-Step

Confirm which Outlook account and version you are using. Open the mailbox that received the sender’s message and note the account address. Outlook can mean Outlook.com, Microsoft 365 work or school email, or the Outlook app connected to another provider. The blocked list may be different for each account, so changing a list in one mailbox will not necessarily change another. On Windows, classic Outlook has a traditional ribbon and a File tab; the new Outlook has a Settings gear and a redesigned interface.
Open the blocked-senders settings in Outlook on the web or new Outlook. In Outlook.com, Microsoft 365 Outlook on the web, or the new Outlook for Windows, select the Settings gear in the upper-right corner. Choose Mail, then Junk email. If the settings pane opens with a search box, search for “Junk email” or “blocked senders” to find the relevant section. In the blocked senders and domains list, locate the address or domain you want to allow again.
Remove the sender from the blocked list. Select the entry and use the remove, delete, or trash-can control shown beside it, then save or confirm if Outlook asks. The control’s appearance can differ between versions. Check the full address before removing it: a blocked domain such as example.com affects more senders than one individual address. If the exact sender is not listed, do not remove unrelated entries; the message may be routed to Junk by another setting or rule.
Use classic Outlook for Windows if that is your interface. In the main Outlook window, select Home > Junk > Junk E-mail Options. In the dialog box, open the Blocked Senders tab. Select the sender’s address or domain and choose Remove, then select Apply and OK. Depending on the ribbon layout, Junk may be displayed as a button or inside a menu. If you do not see Junk E-mail Options, check that you are in classic Outlook rather than the new Outlook app.
Check Outlook for Mac or use the web settings. In Outlook for Mac, open Outlook > Settings (called Preferences in some older versions) and look under Mail for Junk Email or blocked senders. Remove the relevant entry if your version provides that list. Mac layouts can vary, so if the option is missing, sign in to Outlook on the web with the same account and use Settings > Mail > Junk email instead. For a work or school mailbox, the organization may manage some mail protections centrally.
Find messages that arrived while the sender was blocked. Open the Junk Email folder and search for the sender’s address or name. If you find a legitimate message, select it and choose Not junk or Report > Not junk, if that option is available. You can also move it to the Inbox. Check Deleted Items as well if you may have deleted the message. Removing an address from the blocked list does not normally recover mail that was already filtered or deleted.
Send or request a new message to verify the change. Ask the sender to send a fresh email, or wait for their next message. Check the Inbox and Junk Email folders, and allow a little time for delivery. If the new message still goes to Junk, mark it as not junk and continue with the checks in Troubleshooting. If it does not arrive anywhere, confirm the sender used the correct address and check whether your mailbox has a rule, full storage, or an organization-level filter affecting delivery.

Common Mistakes

Changing the list for the wrong account. Outlook may have several mailboxes open at once, and each account can have its own settings. Verify the address shown for the mailbox before editing the list. If you use Outlook with both a personal and a work account, repeat the check in the account that actually receives the mail.

Removing the wrong entry. A blocked domain is broader than a single email address. Removing a domain allows mail from addresses across that domain, while removing an individual address affects only that listing. Read the full entry before deleting it, especially if the list contains similar addresses.

Assuming unblocking restores old mail. Unblocking changes how future messages are treated; it does not automatically bring back messages already in Junk Email or Deleted Items. Search those folders separately and move any wanted message back to the Inbox.

Looking only at the blocked list. A sender can still be filtered by a rule, a mail-flow policy, a safe or blocked list at another service, or an organization’s security system. If the address is no longer blocked but delivery has not changed, check other filtering locations rather than repeatedly removing the same entry.

Tips

Use the exact address shown in the message’s sender details, not just the display name. Display names are easy to change and may be shared by unrelated senders. If a company sends from several addresses, check whether you blocked a specific address or a whole domain before deciding what to remove.

When a message is in Junk Email, use Outlook’s Not junk action as well as removing a blocked-list entry. That action tells the service that the particular message was misclassified. If you see a choice to always trust the sender, use it only when you recognize the address and expect future mail from it; allowing every sender can weaken your spam filtering.

For a work or school account, ask your Microsoft 365 administrator for help if the setting is locked, missing, or reverts after you change it. Organizations can apply filtering and retention policies that take precedence over personal settings. Keep a note of the address you removed if you are troubleshooting several mailboxes, so you can tell which account has been updated.

On a phone, the quickest immediate fix is often to open the message in Junk Email and move it to the Inbox or mark it as not junk. That is not always the same as removing the address from the account’s blocked list. Use Outlook on the web or a desktop version to inspect the full list when the mobile app does not expose it.

Troubleshooting

The blocked-senders list is empty, but mail still goes to Junk. Check the Junk Email folder’s message details and any rules that target the sender, subject, or words in the message. In Outlook on the web or new Outlook, review Settings > Mail > Rules. In classic Outlook, use Home > Rules > Manage Rules & Alerts. A rule that moves or deletes messages can continue to act even after the sender is unblocked. Also check any filtering service or security product connected to the account.

The message is not in Junk Email. Search All folders for the full sender address and check Deleted Items, Archive, and any custom folders. If the sender receives a delivery failure notice, ask them for the notice’s wording; it may identify a typo, a full mailbox, or a server rejection. For work or school email, an administrator may be able to check quarantine or message tracing. Personal Outlook users can ask the sender to verify the recipient address and resend.

You cannot find or edit the setting. Confirm which Outlook interface you have and try Outlook on the web with the same account. In classic Outlook for Windows, use the Junk menu rather than looking only in the general Settings area. If the mailbox is connected to Gmail, Yahoo, or another provider, the provider may have its own blocked list and spam controls; Outlook’s list may not be the only place affecting delivery. Check the provider’s settings as well.

The sender is still blocked after you remove them. Refresh Outlook, sign out and back in, and verify that the change was made to the correct mailbox. Search the list for both the full address and its domain. If the entry returns or removal is unavailable, your organization may manage the list or a policy may be applied centrally. Contact the administrator rather than trying to bypass the control.

A sender’s address changes frequently. Unblocking one address will not necessarily allow messages from a different address, even if the display name is identical. Check each genuine sending address in the message details. Avoid allowing a broad domain unless you are confident that all mail from that domain should be trusted.

Frequently Asked Questions

Does unblocking a sender notify them?
No. Outlook does not send a notification when you remove an address from the blocked list. The sender generally will not know unless you tell them or they notice that new messages are being delivered.

Will unblocking bring back emails I missed?
No, not by itself. Look in Junk Email, Deleted Items, and other folders, then move any message you want to keep to the Inbox. Messages already permanently deleted or expired may not be recoverable.

Can I unblock a sender in the Outlook mobile app?
You can usually move a message from Junk Email to the Inbox or mark it as not junk in the app. The mobile app may not show the full blocked-senders list. If you cannot find that control, use Outlook on the web or desktop with the same account.

What is the difference between blocking and marking a message as not junk?
Blocking adds an address or domain to a blocked-senders list so its mail is treated as unwanted. Marking a message as not junk corrects the handling of a particular message and may help Outlook classify similar mail. If the sender is explicitly blocked, remove that block too.

Why can I still receive mail from someone I blocked?
The sender may be using another address, or the message may come through a mailing list or a different account. Blocking an address does not necessarily block every address with the same display name. Check the actual sender address and whether the message was delivered to the mailbox you changed.

Can my employer prevent me from unblocking someone?
Yes. Work and school administrators can apply organization-wide security settings or quarantine rules. If you cannot change the list or messages remain blocked after a change, contact your IT or Microsoft 365 administrator with the sender address and the approximate time of a missing message.

Try it: the Date Difference Calculator: days, months, years and weekdays between two dates, with the DATEDIF formulas.

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Sources: Function behaviour and menu paths: Microsoft Support documentation for Excel. Method & sources

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