If you are getting the install error "Could not connect: Access denied for user 'xxx'@'localhost' (using password: YES)" when you go to your website url to install:

1) Check to make sure you have renamed your connect_sample.php file to "connect.php"

2) Check that you have updated your "connect.php" file with the correct database name/username/password fields

3) If your database password has a "?" in it - reset it so that it doesn't.