@Asif Naeem Thank you for reaching out to us!
From the screenshots provided, I understand that you are encountering an issue while registering the MABS server. Could you please follow the guidance provided in the troubleshooting article here - https://learn.microsoft.com/en-us/azure/backup/backup-azure-mars-troubleshoot#the-activation-did-not-complete-successfully
If you have already followed the suggestions, then the next step would be to create a new recovery services vault and register the server.
Reference link to a similar discussion here - https://learn.microsoft.com/en-us/answers/questions/513691/mars-register-server-wizard-fails-encountered-an-i
Hope this helps. Please write back to us if you have any concerns.
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