After you restart vCenter Server, when you use vSphere Replication, reprotect operations sometimes fail.

Problem

After you restart vCenter Server, when you use vSphere Replication, reprotect operations fail with the error
Error - Unable to reverse replication for the virtual machine
	 'virtual_machine'. The session is not authenticated.

Cause

After vCenter Server restarts, it fails to refresh some sessions that Site Recovery Manager uses to communicate with vSphere Replication and causes reprotect to fail.

Solution

Restart the Site Recovery Manager services on both of the sites.