Working with pdf files

Hello,

I have several pdf files that I wish you use as give aways. My problem is there are four files that when clicked on generate an 404 error message saying they can’t be found. However, I have several others that behave as they should, they open up and can be read or downloaded.

All the files have been loaded up to my media lib. so I don’t understand why these four act differenctly than the other PDF’s. Does anyone have any insight or can you point me in the right direction to find a fix for this.

Thank you,
Tim