No Authentication after closing the primary Domain controller

 ISSUE:

there are 3 domain controllers on the environment, one of them is the primary DC, when we try closing it, outlook can't authenticate with exchange server.

an outlook prompt keeps appearing

we want to test in case of update or outage that nothing could go wrong

Cause:

The Primary Domain Controller had all FSMO roles including PDC role which is responsible for authentication.

Resolution:

Before closing the DC, we transferred the PDC role to another Domain controller, then shutdown the primary one

To do so please follow:

1. Click Start, point to Administrative Tools, and then click Active Directory Users and Computers.

2. Right-click Active Directory Users and Computers, and then click Connect to Domain Controller (If you on another DC).

3. Do one of the following actions:

   • In the Enter the name of another domain controller box, type the name of the domain controller that will be the new role holder, and then click OK.
     -or-
   • In the Or, select an available domain controller list, click the domain controller that will be the new role holder, and then click OK.

4. In the console tree, right-click Active Directory Users and Computers, point to All Tasks, and then click Operations Master.

5. Click the appropriate tab for the role that you want to transfer (RID, PDC, or Infrastructure), and then click Change.

6. Click OK to confirm that you want to transfer the role, and then click Close.

Other Information:

We also tried to assign a Static domain controllers to Exchange server but this didn't change the behavior