I have been trying to figure this out. We have 3 citrix xenapp 6.5 servers running 2008 server r2. We have this application that has a chm help file that will not open on one of the citrix servers. I have tried the fix for the registry and also re registered the ocx file but nothing works still on the one citrix server to open the chm file. I can copy it locally and it works fine, but I am all out of things to try. Anybody experience this?