Published 2024-11-05 by TechNet New England
An account lockout in Microsoft 365 happens when too many failed sign-in attempts occur. This is a security feature that prevents brute-force password attacks. ## Why Accounts Get Locked **Too many wrong password attempts.** If you (or someone else) enters the wrong password multiple times, the account locks to prevent unauthorized access. **Old password on a device.** If you changed your password but a phone, tablet, or old laptop is still trying to sign in with the old password, each failed attempt counts toward the lockout threshold. **Saved credentials in Windows.** Credential Manager may hold an old password that keeps trying to authenticate. **Shared mailbox or service account.** Multiple people or automated processes using the same account with an old password. ## How to Unlock ### If You Know Your Password Wait. Most lockouts are temporary (15 to 30 minutes). After the lockout period, try signing in again with the correct password. ### If You Forgot Your Password 1. Go to [passwordreset.microsoftonline.com](https://passwordreset.microsoftonline.com). 2. Enter your email address. 3. Complete the verification (phone, email, authenticator app). 4. Create a new password. This only works if your organization has enabled self-service password reset (SSPR). ### If Self-Service Reset Is Not Available Contact your IT help desk. They can unlock the account and reset the password from the admin center. ## Prevent Future Lockouts ### Update All Devices After changing your password, update it on every device: 1. Outlook desktop: it should prompt automatically. If not, remove and re-add the account. 2. Phone email app: update the password in account settings. 3. Teams mobile app: sign out and sign back in. 4. Any other device or app connected to your Microsoft 365 account. ### Clear Saved Credentials on Windows 1. Open **Credential Manager** (Win + R, type `control keymgr.dll`). 2. Under **Windows Credentials**, remove any entries for "outlook," "office," or "microsoftonline." ### Check for Old Devices If you have an old phone or laptop you no longer use but it is still signed in to your Microsoft 365 account, it may be causing lockouts. Sign out or revoke access from [myaccount.microsoft.com/device-activity](https://myaccount.microsoft.com/device-activity). ## Repeated Lockouts You Did Not Cause If your account keeps getting locked and you are not entering wrong passwords, someone may be attempting to access your account. Contact your IT provider immediately. They can: Review sign-in logs for suspicious activity. Block specific IP addresses. Enable additional security measures. Check if your credentials were exposed in a data breach.