Cannot Connect to the Xenapp Server. Protocol Driver Error

Posted on 2009-04-21
Last Modified: 2012-05-06
Hi Guys,

I have number of users experiencing an intermittent problem when logging on to Citrix via the Web Interface (we are using a CAG).

They get the error "Cannot Connect to the Xenapp Server. Protocol Driver Error". During testing  - I published a desktop to just one specific server in the farm. Sometimes it connects successfully, sometimes it fails. If it fails - it will log on successfully with a little patience and persistance.

Session Reliability is turned off on the WI.

Any suggestions?


Question by:boppaluccio1
    LVL 11

    Expert Comment

    Did you confirm proper routing between all clients and server? Ports open accordingly (1494 with no SR turned on)? Also is this using the latest client?

    Author Comment

    Sorry for the delay in getting back to you pfcj.

    Routing between clients and server is fine ports are open appropriately and SR has been turned off. Latest version of the client and happens issue for multiple clients, probably all clients, from numerous locations inside and outside of the company.

    In my test scenario: I'm logging into the web interface via the CAG from my desktop. When launching an application published  only to me and to only one server, it seems to be completely random whether or not it successfully launches or gets the error. We've only one CAG in this setup and nothing changes between attempts to launch. It might work - 5 times in succession then fail, or might fail 5 times in succession, then work. Issue is intermittent and seems random which is making it difficult to nail down.

    I've also tried the same test scenario with another published app, from an alternate desktop and locking it down to a different Citrix server - same intermittent issue.
    LVL 11

    Expert Comment

    Any eventlog entries on the WI/CAG that may point to an issue?

    Accepted Solution

    Rebuilt the CAG

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