Recently I had a high profile customer having a terrible connection experience launching ICA sessions.
I checked the usual suspects like connection timeouts, disabling session reliability, checking for NAT settings and so on. No improvement.
However one thing I observed was launching the ICA session from within the same desktop network did not exhibit this behavior. So it must be something at the level of the client network settings or the ICA file itself.
After some Googling and messing around, it turned out to be Client Proxy settings inherited by the ICA file from the Internet Explorer Proxy settings. The users had proxy settings configured in their Internet Explorer. So the ICA connection first goes to proxy server before making a direct connection and that explains the long delay in establishing the connection.
Configure Client Proxy settings in StoreFront to None instead of the default “auto”. Use this CTX article http://support.citrix.com/article/CTX136516