Hi Kouevi,
Thank you for contacting us through the Microsoft Q&A forum.
Based on your query, it seems you are experiencing difficulty opening the cloud shell instance of the sandbox.
To address this issue, please follow the troubleshooting steps outlined below:
1.Sign out from all tabs in your current browser and clear the cache files. Then, attempt to log in again using your Learn ID credentials.
2.Sign out of your current browser session and try logging in using an incognito window or private browsing mode.
3.Switch to an alternative browser and attempt to log in again.
4.Refresh the page to resolve any temporary glitches and reactivate the sandbox.
5.If you're still unable to access, try logging in with a new personal Microsoft email account using a different browser. If you don't have one, create a free Microsoft account. Remember, you need a Microsoft account like Office 365 or Outlook.com for sandbox access.
If you encounter further challenges, please share relevant screenshots (with sensitive information hidden) for assistance.
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