We have an exchange 2013 server which will be getting decommission/shutdown. All mail users on this server will be setup on a new server on a different domain (not a subdomain). Due to this we are exporting all mail boxes to a file server as psts. Once the users have been setup on the new exchange server and domain we need to copy over their calendar entires to the new mailbox. What's is the best way to do this? As I understand because we are crossing over to a new domain and exchange server we can not just copy and paste the entries from the pst into the new calendar.