Moved WordPress but installer is running

I am trying to move WP 3.2.1 from GoDaddy hosting to Media Temple.

My domain name is not changing and because I’m not bothered about downtime, I have already pointed the nameservers to the (new) Media Temple hosting.

I followed this process to move WP:
1) Downloaded all WP files from GoDaddy
2) Used phpMyAdmin to export database from GoDaddy
3) Uploaded all WP files from GoDaddy to new Media Temple hosting
4) Imported database to Media Temple
5) Edited wp-config for new database settings

When I try to open the site in my browser, the installer begins.

Any ideas why WP is trying to do a fresh install?