Mac and Windows Dropbox problem

My friend and I are working on a unity ios project on a windows computer. We used dropbox to try to move it to my Mac. When we did so, my friend was able to open the project on his windows computer but I am unable to open it on my Mac. Is there a reason that this happens? Is it something that occurs often?

You need source control, ideally subversion.

  1. establish a subversion repo somewhere (free or a small $ per month)

  2. on the mac get

  3. on the PC get a svn client

Find and follow the usual simple instructions for using source control with unity (ignore library folder, set certain options correctly, etc)