The problem that the customer environment actually occurs.
Problem
==============
All Exchange online accounts in the global Office 365 tenant cannot be used, and the Exchange Online management console cannot be opened. When viewing the user information, the remote server returned an error is displayed (404 Not Found) error. When you click the email app, the page displays only white.
Problem analysis
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1. Exchange online can be successfully accessed through other global Office 365 tenant account login tests. Determine Office 365 service issues and are not a network environment issue for customer access.
2. The email address of the Exchange online user is queried in the background and cannot be queried. Prove that the Exchange online account did not provision successfully.
3. As confirmed, we found that this domain name is still tied to the 21V version of Office 365 tenant.
4. If the domain name is bound to a global version of Office 365 Tenant and attempts to bind the domain name to another global version of Office 365 Tenant, an error will be made and cannot be bound. If the domain name is bound to a 21V version of Office 365 Tenant, and you try to bind the domain name to another global version of Office 365 Tenant, you will not get an error and can bind successfully. However, this does not mean that the domain name can be used properly on the global version of Office 365 tenant. This situation may cause problems with the global version of Office 365 tenant Exchange Online users provision.
Workaround
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After completely removing this domain name that is bound to the 21V Office 365 tenant, the effective time is approximately 6 hours, and the current global version of Office 365 tenant Exchange Online new users provision successfully.
This article is from the "Davewilk Technical Thinking" blog, please be sure to keep this source http://jiayu.blog.51cto.com/121732/1761253
About Office 365 domain name binding issues