Sort by attachment

I have an odd problem with one of my EndNote-libraries (EndNote 7.1, Mac). I can’t sort the references by attachment. When I click on the header for attachment, it sorts by Author!

It’s just this one library, there are no problems sorting by attachment in other libraries.

Dear Solvi,

It sounds like that library could be damaged, have you tried the “recover library” command under tools in EndNote? First, close the library then click tools/recover library and browse for the problem library.