I have studied a lesson recently when I try to remove the default domain from my Office 365 Account.

The error displayed as a popup: “Can’t remove the Default Domain”

Following are the procedures I followed:

Microsoft Online Services: Admin->Domains

Select the domain name which you want to remove and click ‘Remove’

Conform the operation by clicking ‘Yes’

Got stuck here 🙁

After some research throgh Office 365 Documentations and troubleshooting helps, I have identified the correct procedure to follow to remove the default domain from my cloud account:

1. Get the domain info of my account: Following cmdlet displayed all domains configured on my cloud account with the details. Is Default parameter of the domain can be seen as True for the default domain.

Get-MsolDomain |fl

2. Delete all mailboxes and DLs associated with the domain

3. I made the one of the other domain as the default domain now

set-msoldomain -name manuphilip.onmicrosoft.com -IsDefault

4. Verified the Is Default parameter again for cross checking the result and found as the other domain is set as default now.

5. Try to run the cmdlet  Remove-MsolDomain now and found as the operation is successfull:

Hope you can go through the procedure, when you are facing a similar issue.