I’m assuming you changed the hostname in the IS to match the new hostname? And was it the actual hostname or the IP address that changed? The JVM caches IP addresses but it should have expired after 4 weeks.
If you can ftp from the command line on the same server as the IS then as long as everything matches (hostname, username, password) you should be good to go.
#Integration-Server-and-ESB#webMethods#webmethods-Protocol-and-Transport