I accidentally removed my device from Microsoft's university account registration.

Hi @mahmoud edreas,

Good day to you! Welcome to Microsoft Q&A.

To resolve the “credential is invalid” error and successfully re-register your device with your university or organization, please follow the steps below:

Step 1: Sign Out and Remove the Work Account

1. Sign out of all Office 365 applications (Word, Outlook, Teams, OneDrive) that are currently signed in with your university credentials.
2. Open Settings > Accounts > Access work or school.
3. If your university account is listed, select it and click Disconnect. Confirm any prompts to remove the account.
4. If the account is not listed, proceed to the next step.

Step 2: Clear Cached Credentials

1. Open Control Panel and go to User Accounts > Credential Manager.
2. Select Windows Credentials.
3. Remove any entries related to your university account or Office 365 services. Look for entries that mention your university email, “Office16”, “OneDrive”, or “Teams”.
4. Also check Generic Credentials for entries like MicrosoftAccount:******@school.edu and remove them.

Step 3: Restart the Computer Restart your device to ensure all background processes and cached tokens are cleared.

Step 4: Re-register the Device

1. Go to Settings > Accounts > Access work or school.
2. Click Connect or + Add account.
3. Enter your university email address and password.
4. When prompted, choose Yes to allow your organization to manage the device. This step registers your device with Azure AD or Entra ID.
5. Complete any additional verification steps, such as multi-factor authentication or Windows Hello setup.

After a short moment, your account should appear under “Access work or school” with a note like “Connected to [Organization Name]”.

Step 5: Sign Back into Office Applications Open any Office application (Word, Outlook, OneDrive) and sign in with your university account. The sign-in should now succeed, and the device will be recognized by your organization’s system.

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