AADSTS900561: The endpoint only accepts POST requests. Received a GET request

Hi @Yogesh Bagga, 

Thank you for posting your question in the Microsoft Q&A forum. I completely understand how frustrating this issue can be, and I want you to know that I’m here to support you. 

Based on my research, the error AADSTS900561 typically occurs when the authentication request is sent using the wrong HTTP method. Azure AD requires POST requests to process tokens and sensitive credentials, but in this case, it received a GET request instead. One of the most common causes is that your browser may be blocking third-party cookies, which are essential for the authentication flow to complete successfully. Another possibility is that your browser’s cache or cookies are outdated, which can interfere with session data and lead to unexpected behavior. Sometimes, certain browser extensions might also disrupt the authentication process. 

Here are some steps you can try: 

1.Enable third-party cookies 

Could you please let us know which browser you're currently using? Here's how to allow third-party cookies for Chrome and Edge: 

• Chrome:  Go to Settings > Privacy and security > Third-party cookies > Select Allow third-party cookies 

• Edge: Go to Settings > Privacy, search, and services > Cookies > Turn off Block third-party cookies 

Note: If you are using other browser, please comment to let me know.

2.Clear browser cache and cookies 

• Clear all cached data and cookies from your browser. 
• Alternatively, try accessing the site using Incognito/InPrivate mode. 

3.Add login URLs to Trusted Sites 

• Open Internet Options 
• Navigate to the Security tab > Select Trusted sites 
• Add: https://login.microsoftonline.com and any other Microsoft endpoints you use 

4.Try a different browser or device: This can help determine if the issue is browser-specific. 

Please understand that our initial response does not always resolve the issue or meet fully expectation immediately. However, with your help and more detailed information, we can work together to find a solution.   

If you have any updates, please feel free to leave a comment under this post. I’ll be happy to assist further. 

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