@Fritch94 I ran into this exact problem after upgrading FOG to the latest svn. It took me a while to track it down, but this solution worked:

https://forums.fogproject.org/topic/3433/unable-to-upload-first-image/5

It was a suggestion Tom made a while ago to another user with similar issues. Replacing pxelinux.0 with a sym-link to ipxe.kpxe did the trick for me. Hopefully it will work in your case.