Thanks for this information. I have I think a unique issue. I have exchange 2010 (2 CAS and 2 Mailbox) servers and working on migrating to exchange 2016. (stage 1) On-Prem. We have 2016 up and running and in control with all active user mailboxes moved to 2016. Here is the question. These 2010 servers are in a DAG config but we had a breakage of the secondary server set and lost the VM drives for some user DB's and the drive for public polders. As we are ready to migrate the public folders to the new 2016 exchange using MS tools for this can we just remove the DAG for the public folder DB then proceed with the migration. We have exported all data in the public folders before we started. In addition to this the size of the PF is over 173GB. Yes we cleaned up as much as we could. It started at 2.6TB. How do I safely proceed?