Block user sign-in in Microsoft 365 Lighthouse

You can block a user account if you think it's compromised. When you block a user account, it immediately blocks anyone from signing in to that account. If a user tries to sign in, they're automatically signed out of all Microsoft 365 services within 60 minutes. Blocking a user account won't delete any data, and it won't stop the account from receiving mail.

Block sign-in for a user

  1. In the left navigation pane in Lighthouse, select Users > Account management >Search users.

  2. On the Search users tab, enter a user's name in the search box.

  3. From the search results list, select the user.

  4. In the user details pane, select Block sign-in.

  5. In the Block sign-in pane, select Block this user from signing in.

  6. Select Save changes.

Block sign-in for risky users

  1. In the left navigation pane in Lighthouse, select Users > Risky users.

  2. On the Risky Users page, select the set of users you want to take action on.

  3. Select Block sign-in.

  4. In the Manage sign-in status pane, select Block users from signing in.

  5. Select Save.

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