If you did not use the correct company name when you first signed up, your SharePoint URLs for your sites will continue to use that name when you create new SharePoint sites. SharePoint URLs in your Microsoft 365 environment are created based on your fallback domain name. They want to change how their SharePoint URLs look like when they create a new site.Now that they know the company name, they want their users to have login account names that are appropriate. Not knowing the company name to use when they first signed up for Microsoft 365.Common reasons customers change their fallback domain include:

You can change your fallback domain in the Microsoft 365 admin center. Even if a custom domain is used (for example, ), if that custom domain is deleted from your Microsoft 365 environment, the fallback domain ensures that your user's email is successfully routed. When a user is set up with a mailbox, email is routed to the fallback domain. It serves as a default email routing address for your Microsoft 365 environment. Microsoft 365 teams & groups email aliases.Your fallback domain is used by default in: When you sign up for Microsoft 365, Microsoft provides an domain - your fallback domain - in case you don't own a domain, or don't want to connect it to Microsoft 365 (for example, ). Check out all of our small business content on Small business help & learning.

Changing name on microsoft account