I am getting this error when I click on the "References" tab when I am about to open a file within SW: "Cannot edit file references. Either the file is not a valid SolidWorks document or it has not been saved in SolidWorks 97 or later."
The assembly was made with 2013 and is obviously a SolidWorks file. What could be wrong?
Are you opening through SW or through Windows Explorer? Perhaps try the opposite?
Tried restarting computer?
Do you have another computer you could try it on?