T10 - Connection Error when Launching Applications - XenDesktop 7

Have a test environment with XenDeskop 7 and trying to connect via a T10, running ThinOS 7.1_122

I am able to log in fine, see my applications, but when I click on one to laugh I get the following:
Connection Error. The published application currently is not available. Try connecting again later.

On the event log on the T10 it says:
ICA: terminated, status 0x1
ICA: connection closed by server.

The root and intermediate certificates are loaded and we don't get any errors with them. I can also launch applications fine from a PC or remotely, ie from an iPad. I am running XenApp 6.5 on these and it runs fine.