Today i had installed Oracle 11g release 2 version on my system and found that listener service is created but not able to start(..giving an unusual error like some services stop automatically if they have nothing to do).
I have followed the below steps to solve this..
1.) Tried executing the listener service manually by running D:\app\Vishwanath\product\11.2.0\dbhome_1\BIN\TNSLSNR.exe
2.) I found the message "ORACLE_HOME not set".
3.) I immediately set the same in Environment variables by going to My computer-->Properties-->Advanced.
4.) Took a restart of the machine.
5.) Tried restarting the listener service again and this time successfully started.