I have go daddy too and I've spent about 12 hours over the last two days trying almost everything that's been suggested on this site. I still can't get it to work.
One thing I notice. If I click on the readme page via FTP to open the install.php I get an error that says it can not find the wp.config file, and that I've already installed wordpress. If I try to log directly into into the install.php outside of FTP, http://xxxxxx.com/wp-admin\install.php I just get a page not found.
After reading the posts here I've come to the conclusion this can't be done on Godaddy if you are running Windows on the economy plan.
You have to switch to linux or upgrade to the delux plan. Anyone know anything different?