Setting up the new server meant we needed to use a new host name for the new server. Restoring from the old server I am now finding emails generated by website forms on the new server using the old hostname. And because of this they are seemingly getting stuck in the mail queue. There are only a few there at the moment with the status of unknown mail transport error, but looking at the headers the receiving server is listed as the old host, not the new one.
I was wondering if there is a simple way to fix this. Somehow the configuration files of the Virtual Servers need to be updated to the new server but I'm not sure how to go about this?