I had the same problem and the LinkMachineName Setting in the config.xml from the webserver was my solution.
It's also possible to fix this problem with an etc/hosts hack. You have to add your internal server with the external ip to the etc/hosts file on the client pc. I get this fix from the Qlikview support. But if the IP or the hostname changes you have to update all hosts files.
My question is, why is the LinkMachineName setting not reachable from the Enterprise Console? And why is there the wrong hostname?