Changed DB name/user – Everthing ok Except Login

hello, i’ve changed my account information on the host account so my DB name changed so the DB user name. All the files remain on the same account untouched. i updated the config file with the new data and the blog is working ok but it returns to me a WHITE BLANK PAGE after i try to login.

I have no idea what else should i change…

Thanks

PS: 2.7.1