The File formats are not compatible. You need to be either both use FileMaker 12 or both use FileMaker 11.
The File Formats are not compatible. But you can convert FM 11 to FM 12 (not the other way around), unfortunately doing that means that not everything is the same (although a lot is).
In any case, It would be better if you were to have both or the same versions.
Good point. Sometimes we forget the obvious.
You can also send the data from a database of one version to a database of the other if you export the data from file 1 to one of the many file formats available (Excel, tab, csv, merge) and then import the data into file 2.
Thank you Phil, IT_USer,. I sure appreciate your response.