My problem seems to be the exact replica of the question already discussed on " Title:UNABLE TO CONNECT TO DATABASE".
I am posting this question again, as, there was no solution found for this question in that thread. Please redirect me, if there is another thread, which I can refer to fix my issue.
To briefly summarize the issue i am facing:
 Installed Microsoft Loopback Adapter
 Installed Oracle 10g on my laptop (Windows XP) => ORACLE_HOME = C:\Oracle10g\product\10.2.
 Global Database Name: WMLOCAL / Pwd: wmlocal
 At the end of the installation, an error was displayed that EM Cannot be started.
 Changed all the password to a common one = wmlocal
 Installation completed.
Now, when I try to perform:
[a] tnsping wmlocal => I get TNS-12535: TNS:operation timed out
[b] Try to Start the Service "OracleDBConsolewmlocal" => Fails with timeout. (Screenshot attached)
[c] lsnrctl stop & start worked without any exception
[d] lsnrctl status => File Attached with the output.
[e] sqlplus system/wmlocal@wmlocal as sysdba => ORA-12170: TNS:Connect timeout occurred (output attached)
Note 1: Attached are my tnsnames.ora, listener.ora & sqlnet.ora files
Note 2: Already re-installed couple of times from scratch, but no luck.
Your inputs/help is very much appreciated.