'Connecting to Server' has encountered a problem

I’m trying to connect my designer workstation 9.6 to my local IS and running into an issue. I was able to connect to this IS previously. I have confirmed that the IS is running. But every time I attempt to connect now I get the following error:

‘Connecting to Server’ has encountered a problem

Connection failed for (java.lang.ClassCastException)
java.lang.String cannot be cast to com.wm.data.IData

I’ve tried specifying localhost and the IP address.

Share your OS details? For me this is not a permanent issue (might be a network or firewall block). Check your windows firewall.

Can you refer this link: http://serverfault.com/questions/26564/how-to-check-if-a-port-is-blocked-on-a-windows-machine

If the issue still exists, you may uninstall and re-install. Post me your comments.