Hi,
I was finally able to resolve my problems, and I'm hoping that the information I provide here will assist someone:
1. Uninstall Oracle client, removing folder C:\Oracle

2. Remove all Oracle entries found in the registry under Hkey_Local_Machine.

3. Enter registry and navigate to HKeyLM\system\CurrentControlSet\Services\Winsock. Delete the Winsock Key.

4. Navigate to HKeyLM\System\CurrentControlSet\Services\Winsock2. Delete the Winsock2 key.

5. Uninstall TCP/IP - Reason is because the winsock libary is corrupted and as a result Oracle cannot resolve your tns entries properly. After uninstall restart pc.

6. Reinstall TCP/IP

7. Reinstall Oracle and perform the necessary configuration.

After you've done the necessary configuration, everything should be ok.
If you encounter any problems, please send me an email at ramdattk@candw.lc, and I would be more than happy to assist you in resolving any issues relating to this problem.

Cheers
Kenty