All customers fields in ADMIN > CUSTOMERS are empty and I can't delete them!

All the customers fields in ADMIN >> CUSTOMERS are empty and I can't delete them. Also, when customers are trying to login, they can't... It tells : Error: Sorry, there is no match for that email address and/or password.

I open my e-store on march 1st!

Thank you for your help and sorry for my bad english... I'm a french canadian!

Pierre-Luc

First steps:

1. Check your MySQL database. Is it intact?
   

   Check the customer, orders and address book tables. Is there data?

   
   If there is no data try restoring your database from a backup.

2. Can ZenCart access the database? (You would likely have gotten error messages if it could not).
   

   If not, check your database paths in /includes/configure.php and /admin/includes/configure.php