Problems with Php/CMS/Flash

I'm not too sure what the hey is going on. I updated some pdf's and uploaded them. Now heres the wierd thing. I went to the site proper, clicked on the link to pdf#1 and it says:

"Sorry, Forbidden.
You don't have permission to access this URL on this server.

Additionally, a 410 Gone error was encountered while trying to use an ErrorDocument to handle the request.

Please check the URL for proper spelling and capitalization. If you're having trouble locating a destination on Yahoo!, try visiting the Yahoo! home page or look through a list of Yahoo!'s online services. Also, you may find what you're looking for if you try searching below."

Strangely, Pdf#2 and #4 work.. but Pdf#3 and #5 don't.

I don't know what im doing wrong, i thought Flash cs4 and CMS were to make web updating easier. please help!

Thanks.