Wow thanks for solving this. Hopefully this won't cause any other problems. Can someone explain to me why a new install would have this issue? Is this a silverstripe bug or a problem specific to server configuration?
I was having exactly the same problem with SilverStripe v2.4.3 as soon as I uploaded the site to my host (bluehost).
Following the link in the previous post (by silverRay above) and making the suggested change to /assets/.htaccess fixed it for me.
Change the line:
# Turn the PHP engine off php_flag engine off
<IfModule mod_php5.c> # Turn the PHP engine off php_flag engine off </IfModule>
Thank you D-L, and all previous posters. This solution is simple, and it works!
I had this problem using the one-click installation on GoDaddy v2.4.3. Glad to not have needed to search too hard for a solution.