Hi C S,
Thank you for contacting us from the Microsoft Q&A forum.
I appreciate you reaching out regarding the issue you are experiencing with accessing the Learn Sandbox for the AZ-900 Learning Path. I understand how frustrating this can be, and I'm here to help you resolve it.
The error message you got shows that your account is not recognized as an external user in the Microsoft Services client, which is necessary to access the sandbox. Now, one of the options could be creating a new account; however, I'd like to propose a few troubleshooting steps that might help you use your current account:
1.Log Out and Clear Cache: Please log out of all tabs in your current browser and clear your cache. After doing this, try logging in again using your Learn ID credentials.
2.Incognito/Private Browsing: If the issue persists, please sign out of your current browser session and attempt to log in from an incognito window or private browsing mode. This can sometimes bypass any session-related issues.
3.Different Browser: Alternatively, you may want to try accessing the Learn Sandbox using a different web browser to see if that resolves the issue.
4.Account Selection: If you have multiple accounts associated with your Microsoft services, please ensure that you have selected the correct account before creating resources in the portal. The Azure portal typically defaults to the Default Directory, which may not have the necessary permissions.
5.Account Type: You can sign up for Azure with a personal Outlook or Microsoft account, which may be easier to use and will not have all the restrictions associated with other email addresses.
If you are still having trouble, please let me know, and I will be happy to assist you further.
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