Changing Fully Qualified Internet Host Name

Our fully qualified internet host name does not match what we have in our DNS. If I change our fully qualified internet host name in the server document, will this affect mail routing or have any consequences elsewhere?

Subject: Changing Fully Qualified Internet Host Name

Changing that field will not impact the system. I had it 100% false on a server for months without any problem.

Changing the Hostname in Internet Protocols >HTTP may have an impact.