Can't login

I had download a project from live server. I am success fully run this project but I can't login in my application.
Please someone help me.

hi
Please let us know the following:
- what login mechanism are you using? custom login or some login library?
- have you also set up the database for the project/login locally as well?
- version on CI and PHP and platform and database if you use one

Error messages will be necessary for any of us to help you.