Symptoms or Error
A Citrix XenApp License acquisition error (-5) is generated after connecting a XenApp 6.5 (or earlier) environment to the 11.16.3 build 28000 License Server and 11.16.6 build 31000 License Server.
Solution
The License Server does not support concurrent licensing using XenApp 6.5 or earlier.
The fix is included in license server 11.16.3 build 29000 and 11.16.6 build 32000
The fix is included in license server 11.16.3 build 29000 and 11.16.6 build 32000