Joomla 1.5 login

I am just a newbee at joomla, have searched for help through forums for two days now. Tried to get help. I hope I will get help here? I have joomla 1.5 registration worked fine. Then used CB 1.4 registration and login which I uninstalled. Now joomla login do not work no matter what I do. I installed The love factory dating component which I should think use the joomla default login and I set love factory registration. but now the joomla login from brings up a blank page with no error details just a blank page, registration brings up the page to register but does not add users to joomla user manager owever Admin get email to say a new user开发者_如何学运维 has registered.

Please help Thanks

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if you wanna to know that what the error is then Joomla have a great facility,

GO to Global parameter->server and select the error type = maximum level, and then refresh the page,

You will see your error.