SharePoint Online _api/contextinfo 401 error

3 min read 04-10-2024

SharePoint Online _api/contextinfo 401 Error: Troubleshooting and Solutions

Have you encountered the dreaded "401 Unauthorized" error when trying to access the /_api/contextinfo endpoint in SharePoint Online? This error can be frustrating, especially when you're just trying to gather basic information about your site. Fear not! This article will walk you through understanding the error, analyzing its causes, and providing solutions to get you back on track.

Understanding the Problem

The /_api/contextinfo endpoint is a valuable tool in SharePoint Online. It provides crucial information about the site, including:

Site URL: The full URL of the current site.
Web URL: The URL of the current web within the site.
Site ID: A unique identifier for the site.
Web ID: A unique identifier for the web.
Form Digest Value: A token required for certain operations, like creating or updating content.

A "401 Unauthorized" error when accessing this endpoint means that your request is not authorized. This could be because:

Incorrect Credentials: You are using incorrect usernames or passwords, or your credentials have expired.
Insufficient Permissions: The user account you're using may not have the necessary permissions to access the /_api/contextinfo endpoint.
Incorrect Authentication Method: The authentication method you're using might not be supported by the endpoint.
API Access Restrictions: The site might have restrictions in place that prevent access to the endpoint.

Scenario and Original Code

Let's imagine you're trying to retrieve the site URL and web URL using a simple script:

const request = new XMLHttpRequest();
request.open("GET", "https://yourtenant.sharepoint.com/sites/yoursite/_api/contextinfo", true);
request.setRequestHeader("Accept", "application/json;odata=verbose");
request.onload = function() {
  if (this.status >= 200 && this.status < 400) {
    const data = JSON.parse(this.response);
    console.log(data.GetContextWebInformation.FormDigestValue);
    console.log(data.GetContextWebInformation.SiteUrl);
    console.log(data.GetContextWebInformation.WebUrl);
  } else {
    console.error("Error: ", this.status);
  }
};
request.onerror = function() {
  console.error("Request failed");
};
request.send();

This code uses a standard XMLHttpRequest object to fetch data from the /_api/contextinfo endpoint. However, if you run this code and encounter the "401 Unauthorized" error, it's time to troubleshoot.

Analysis and Solutions

Here's a breakdown of the most common causes for this error and how to address them:

Incorrect Credentials: Double-check your username, password, and tenant URL. Ensure you're using the correct login information for your SharePoint Online environment.
Insufficient Permissions: To access the /_api/contextinfo endpoint, your user account needs at least "Read" permissions on the site. You can verify and update permissions using the SharePoint Online admin center.
Incorrect Authentication Method: SharePoint Online supports various authentication methods, including:
- Basic Authentication: This method is generally discouraged due to security concerns.
- OAuth 2.0: The recommended method for modern applications, requiring an app registration and access token.
- App-Only Authentication: Allows applications to access data without user interaction.
If you're using an outdated authentication method, update your code to utilize OAuth 2.0 or app-only authentication.
API Access Restrictions: Certain SharePoint Online sites might have restrictions in place that block access to the /_api/contextinfo endpoint. This might be due to security measures or specific configuration. Check if your site has any API access restrictions or consult with your SharePoint administrator.

Additional Tips

Clear Cache and Cookies: Sometimes, outdated browser cache or cookies can interfere with authentication. Clear your browser's cache and cookies before trying again.
Test in a Different Browser: Test your code in a different browser to rule out any potential browser-specific issues.
Use Developer Tools: Utilize browser developer tools (like Chrome DevTools) to inspect network requests, headers, and responses for more detailed insights into the error.

Conclusion

The "401 Unauthorized" error while accessing the /_api/contextinfo endpoint can be frustrating, but by carefully analyzing the causes and applying the appropriate solutions, you can overcome this hurdle. Remember to prioritize security, update your code to utilize the latest authentication methods, and consult with your SharePoint administrator if you encounter persistent issues.

SharePoint Online _api/contextinfo 401 error