I believe this is built into Windows, not Word.




It would appear to be a fault in the other program which should be importing the file, not opening it for editing.

Charles is correct--it appears to be a problem with the adobe program (shocker, I know). If you attempt to open an already open Word document in an Office program, you are told it's locked and are given options, including viewing the document in read-only mode.

Immediate options would be to either close the file in Word and then open in the other program, or make a copy of the file and open that in the other program.