Not sure but you could try deleting the .htaccess file.
I’ve then been able to install magento on a Fasthosts Shared server with a Shared MySQL database.
I initially experienced the same issue, being new to php and the magento, have to say wasn’t the best of starts but with a little trial and error i’ve been able to get things sort of working. I’m pretty much a newbie on PHP so please don’t mistake me for an expert.
I found i couldn’t run anything until i deleted the .htaccess file. Since removing that file i could run the magento-check.php file which states apart from MySQL not being installed on the server, everything else is ready to go.
I ran the installer and the home page loads but none of the links work. I just get 404 errors.
I tried to re-upload the .htaccess file, but then get an internal server error. Through a process of elimination and this forum, i’ve found if you comment out lines 116 & 117
## enable rewrites
# Options +FollowSymLinks
# RewriteEngine on
And go into Admin Panel > System > Configuration > Search Engines Optimization > Use Web Server Rewrites > NO
This gets the site working but you have links like:
This image content is still not displayed on the internal pages and i don’t like the fact index.php is in the URL so i’ll continue to try and find a solution. If anyone out there can help, i’d appreciate it!