I have a 2 Windows machines networked and I am having trouble with simultaneous access to files. I would like only one user to be able to open a file at a time, which I thought was automatic, using file locks.... if the program used to access the file is locking the file.

I believe the problem I am having is some of the programs I use, don't lock the file, and there for can be modified simultaneously by multiple users, which is very much not desired.

Currently I am having this problem with only two computers, although as soon as I can figure out a solution to this problem the network is going to be expanded to 6 computers, which will include Windows 7, Vista, and XP, as well as a central file server (Samba).

Is there a way to ensure that all files opened in windows get locked? Any suggestions are appreciated, thanks.