So you can log in via the web and can see everything OK, but the client, logging in the same way can’t see the site at all – or can see the login pages/front page but can’t login?
He can see the login page but it tells him that his user/pass is invalid. And when he submits the form to reset the password, it said his email did not exist.
I was even able to login to the WordPress admin area on my Android smartphone so I am just baffled at how the buyer is having problems.
At this point, I think I am just going to reinstall WP on his server and add the posts back manually. There aren’t very many and the site isn’t customized much.