Files are not showed in Finder Recently, I noticed that on the files on my external hard drive are not shown in Finder. All folders can still be navigated, but the files are not visible. When I check the contents of these folders in terminal, I can see the files are still on those locations and can also be opened with VLC for example. 

Does anybody know what the issue could be? I only found one similar question, where they suggested that the com.apple.IconServices was causing the problem, however the proposed solution did not help in my case.

I am working on OSX 10.8.5.
I realised that the only volume I was having issues with was a NTFS-formatted volume, for which I use Paragons software to write to the volume. I searched for a solution to my problem and found someone having the same problem:
http://forums.macrumors.com/showthread.php?t=1280829

It turns out Paragon writes the files with read, write flags, AND also the execute flag, which causes the files to not be recognised by the Finder. To solve this, you simply have to put the flags to read and write using chmod 644.

Thanks for all the help!