File not modifyable
I have a friend trying to open and use a program I made using Filemaker Pro. I have tested the file on several computers and it works fine for me but when he tries to use it, by selecting from a drop-down box or entering data in one of the fields, he gets a message "this file is not modifyable". I had him check that the file is not marked read only, and the permissions are all correct, etc, but somehow it does not work. He is using W7, whereas all I have to work with is XP and Vista, but he normally does not have trouble with legacy programs.
Has anyone seen this type of error message, and could suggest an answer please?