I run the upgrade.php file and i check put in maintenance mode and bckup tables and I get page cannot be displayed when I proceed??
I assume from this you are putting your forum into maintenance mode "before" your upgrade? Post any error messages or screen that you may see as you attempt to upgrade.
I do exactly as the readme says. Upload all the files then go to the http://yourdomain.com/Forums/upgrade.php
I check the buttons I want to check (backup and put into maintenance mode) then hit the button to continue and it says "page cannot be displayed"