Installation problem – install.php is blank

Hi,
I downloaded 2.8.4. version, went step by step – uploaded everything, changed wp-config.php with my database details, generated security key.
Browsed to file install.php – but it’s a blank page.
Here is my url address:
http://www.businessexchange.ca/blog/wp-admin/install.php
Checked several times – didn’t find a problem.

Thank you in advance

Tali