Cannot login with default user in EP 5.0

Hi

I currently using the EP 5 SP 5 portal. I created a new configuration to login to the portal. But i am not able to login using the new configuration. Strangely the Default configuration is also not being authenticated now. So I deleted the Default configuration registry key and restored it using the PasswordRestore.exe application. I am still not able to login with the Default Configuration.

I have tried restarting the IIS Server, J2EE Engine and the machine itself all in vain.

Could anyone suggest what i may be missing out?

Thanks in advance.

Regards

Priya