Can’t select database – error

Today I moved wordpress from one server to another. I followed the steps from:
http://codex.wordpress.org/Moving_WordPress#Moving_WordPress_to_a_New_Server
http://www.tamba2.org.uk/wordpress/move2/
http://www.tamba2.org.uk/wordpress/restore/

Everything went well. I have created a new database, username, password (which are all the same, so I don’t need to change my wp_config). And then I imported the backup database in phpMyAdmin. And then I transfered every other file onto my new server.

HOWEVER, when I try to access my blog, I get this error

Can’t select database
We were able to connect to the database server (which means your username and password is okay) but not able to select the preps_wp database.

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That database exists and with the same name and content because I am looking at it right now.

What is the problem then? and how can I fix it?

Thank you in advance.