Moving WP – Switching hosting, pls help

I have recently switched hosting companies and am trying to transfer my wordpress site onto my new hosting.

I have 3 wp installations and phpbb forum totalling 4 databases.

I have 2 of the three wordpress installs working perfectly and the phpbb forum works fine, i manually copied all the files and databases.

However, one isn’t working, when I go to the page it tells me:

It doesn’t look like you’ve installed WP yet. Try running install.php.

I am at a bit of a loss, I deleted the database, re-copied it, checked the wp-config, re-copied the files… what can I try to get this working?

Any help would be so good as this is a site for a not for profit organisation and I need it up soon.

Currently I have saved the homepage as an HTML file taken from the Google Cache

http://www.pet-detectives.co.uk