Your client is not of the correct version for communication with this server. You can get the latest from http://www.xibo.org.uk
how to solve this problem??
You need to run a Player that is suitable for the CMS version you have.
What CMS version are you running?
iam using v 1.4. and i download the latest version , solved the problem…thanks 
The last version for Windows for 1.4 CMS is here:
https://launchpad.net/xibo/1.4/1.4.2
You should think about upgrading your whole system though as 1.4 is really quite old now!