lo exception: The Network Adapter could not establish the connection

All,

After installing the Oracle 11g in Windows 7, I have created the new schema(s). Once i created the schema also installed the Oracle Sql Developer.
I created the new connection i entered the connection details but am not able to connect through the Oracle sql developer. I am able to connect through sqlplus.
while try to connect through the oracle sql developer am getting the error. 
lo exception: The Network Adapter could not establish the connection

sql developer was trying to connect to "localhost" (which it always had done successfully in the past), however when I checked my tnsnames.ora file, I noticed the address was my pc's actual windows name. I changed the setting in sql developer from localhost to this name and it not connected.

Solution:
Finally i delete the listener.ora file from <>\app\oracle\product\11.2.0\server\NETWORK\ADMIN and i stop and start the oracle listener(s) in services.

Thanks god :) it works fine. Am amble to create the new connection in oracle sql developer and connected.