Hi @ TA.Saurabh.Singh ,
Will removing a domain delete data (emails) in this process or moving emails to .onmicrosoft?
Exchange Online mailbox data is stored in the datacenter region associated with your Microsoft 365 subscription:
Microsoft 365 data locations - Microsoft 365 Enterprise | Microsoft Learn
Therefore, removing a domain from Microsoft 365 does not delete the data (email) associated with that domain.
The point is I’m using the same domain username (As global admin) to remove the domain so how can i login back again if anything changes or to procced further on removal process?
When you edit the domain for your account, you'll have to log out and log back in using the new domain you chose to continue.
To remove yourself from the domain and log back in, follow these steps:
1. Go to the admin center.
2. Go to Users > Active Users, and select your account from the list.
3. On the Account tab, select Manage username, and then choose a different domain.
4. At the top, select your account name, then select Sign Out.
5. Sign in with the new domain and your same password.
(Kindly note: Administrator accounts can also log in with an onmicrosoft address.)
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