Error establishing database connection after Server Change

I had a WP blog running on my site for many months and it worked fine. A few weeks ago, I transferred my site to a virtual private server. I exported my mySQL database containing the blog off the old server and then imported it onto a newly created database on the new VPS. I uploaded all my WP blog’s files to the server as well.

When I tried to access my blog’s URL on my browser, though, a message stated a database connection could not be established. I made sure the config.php file had the correct database name, user and password and re-uploaded it to no avail. Now, a week later, when I try to access my blog’s url, nothing shows up. Just a blank page.

I can’t access WP at all. I’ve contacted my host and they’ve said all the files are there. They think it’s a php problem. But I didn’t change anything except check the config.php file.

Does anyone have an idea on how to fix this problem? Thanks in advance!