Kindly Stop the Output Messenger Server and Copy the following files and folders from the old server's Output Messenger Server installation path.
5.Chat History Log storage folder
(If saved Log in server refer : http://support.outputmessenger.com/centralized-log-storage/)
Then Download the Output Messenger latest Server V#1.6.10 from the following link and Install in the new destination server
Now paste the Copied files and folders in the new Server's Output Messenger Server folder.
Start the Output Messenger Server Services.
Please make sure that the Output Messenger Clients are pointed to the newly installed Server IP address.
Make sure that you have provided Chat History Log Storage Path in newly installed Output Messenger server.
Also, kindly make your users to use the latest Output Messenger Client Version #1.6.5 from the following link
Hope this helps you.
Thanks for your patience.