Disable replication in mapi network :

Hi mohemedd93,

The error code 0xe0434352 indicates that the MAPI network is still in use by Exchange. To disable replication on the MAPI network, you must first stop all Exchange services on both servers.

To do this, follow these steps:

1. Open the Exchange Management Shell (EMS) on both servers.
2. On each server, run the following command:
   
   

Stop-Service MSExchangeIS​

1. Once all Exchange services have been stopped, run the following command on both servers to disable replication on the MAPI network:

Set-DatabaseAvailabilityGroupNetwork -Identity DAG\MAPIDAGNETWORK -ReplicationEnabled:$false -IgnoreNetwork:$true

1. Once replication has been disabled, you can start the Exchange services again on both servers.
   
   

If you are still unable to disable replication on the MAPI network, you can try the following troubleshooting steps:

• Make sure that the MAPI network is not being used by any other applications.
• Make sure that the MAPI network is not configured as a default gateway on any of the servers.
• Try disabling replication on the MAPI network using the Exchange Control Panel (ECP).