Have you guys ever attempted to connect your SharePoint site and suddenly seen the “SharePoint 401 Unauthorized” message? If “Yes” is your answer, then this guide is for you!
It gets very annoying, right? But don’t fret because you’re not a lone wolf. This error means that the connection request was blocked or the SharePoint didn’t accept your credentials due to security settings.
In Simple Terms, SharePoint is prompting the user to verify their identity, as the current access credentials are not recognized.
The mistake commonly happens when:
- You’re accessing SharePoint Online or On-prem over a browser.
- Running backup tools or migration.
- Integrating third-party apps
- Linking via PowerShell or REST API
Now let’s look at the problems and their remedies one at a time.
Why does the SharePoint 401 Unauthorized Error arise?
There are many reasons following the issue, but here are the most familiar ones:
- Your password or token is out of date.
- Wrong permissions, like your user or app lacks genuine access rights.
- Your connection is targeting the wrong endpoint, or in a simple way, an incorrect URL or site path.
- Your app’s client ID has expired.
- A user browser cache or cookie conflict can cause a 401 unauthorized error.
So, in short, the SharePoint 401 unauthorized error usually shows when your authentication attempt fails, either due to false login data or the SharePoint rejecting the used method.
How can you fix the SharePoint 401 Unauthorized error?
Let’s start from simple to advanced.
1. Confirm Your Login Credentials
This might sound plain, but it’s the most obvious cause.
- Try to log in directly through the SharePoint web portal.
- Make sure that the Multi-Factor Authentication (MFA) isn’t blocking the access.
- If you’re using an app password or API key, double-check it hasn’t expired.
Tip: Update your Microsoft 365 password in all connected apps and PowerShell sessions.
2. Verify the SharePoint URL
A lot of users accidentally link to the wrong endpoint.
- For Admin access, use:
➥ https://yourtenant-admin.sharepoint.com
- For SharePoint Online, use:
➥ https://yourorganization.sharepoint.com/sites/sitename
3. Double-check permissions and access rights
SharePoint permissions can get complicated even for an admin.
- Ensure that you are a site owner and have full control.
- Make sure that the Azure AD permissions of the app you’re using are approved.
- Navigate to SharePoint Admin Centre, then Active Sites, then Permissions to review access.
4. Reissue or Refresh your Access Tokens
When you connect through APIs or scripts:
- Refresh the OAuth access token.
- Refresh the proper scope, like “SharePoint.AllSites.FullControl”
- Delete all cached tokens or saved sessions.
This is very helpful when the SharePoint 401 Unauthorized error occurs in migration tools or automated scripts.
5. Examine Authentication Techniques
Lately, Microsoft has no Basic Authentication across holders for finer security. So, if your utility or script still utilizes a legacy technique, then upgrade it to Modern Authentication (OAuth 2.0).
Access or manage SharePoint On-Premises:
- Open IIS Manager and navigate to the Authentication feature.
- In the Authentication feature check Window Authentication setting is enabled.
- Lastly, restart IIS after changes.
6. Clean Your Browser and Client Cache
Once in a while, the browser saves expired tokens.
- Clean up your cookies and cache in your browser.
- Try incognito mode.
- Clean your stored credentials from the Windows Credential Manager for PowerShell or apps.
7. Reconnect or register the App.
When you use the Power Apps or a migration tool, try:
- Uninstalling and Installing the SharePoint connector.
- Re-upping your Azure AD app and allowing permissions.
- With the latest credentials, reauthenticate your tool.
Putting a stop to future 401 Unauthorized errors:
Once you fix the error, here’s how you can stop it from happening again.
- Users should avoid using encrypted passwords in their scripts.
- You have to ensure that your organization’s authentication setting follows Microsoft’s latest security update.
- Use HTTPS to keep your connection trusted and safe.
- Keep a record of which apps and users have access to which sites.
In simple terms: You have to keep your logins fresh, settings secure, and there you go, your SharePoint connections will run smoothly without the 401 error.
Conclusion:
The SharePoint Unauthorized error can look like a big barrier, but it is just a hint of misunderstanding between your credentials and the SharePoint authentication structure. Whether it’s an incorrect password, an expired token, or outdated authentication techniques, a few checks can get things back on track.
So, by confirming your credentials, updating to the latest authentication, or refreshing your access tokens, you can stop this issue from happening again.
Last Tip: If you see 401 Unauthorized error shows up during a SharePoint Migration, try the Shoviv SharePoint Migration Tool. This tool uses secure modern authentication techniques to ensure a smooth and error-free migration event.
Frequently Asked Questions:-
Yes, this error is fixable via steps, by correcting permissions, clearing your browser cache and cookies, or double-checking authentication and network settings.
When a server receives a request that it can’t confirm because you don’t give the genuine permissions or valid login credentials.
First, you have to confirm the URL, then clean your browser cookies and cache, and you have to try logging out and getting back into the site.
You can try using the Shoviv SharePoint Backup Tool for this task. With its easy-to-use interface and scheduling backup feature, you can easily back up your SharePoint data according to your needs. It will automate the backup that will come in handy in unfortunate scenarios.
