[QUOTE=codeorder;1748543]I have no idea(s) regarding "network.share", though here is a suggestion.
Have a small sidekick.app installed on each user's p.c., that does the "copy and overwrite the existing application executable in the program files\app directory".
I'm not sure how systems work with network.sharing, though there should be a folder somewhere, where everyone can access it.
If it does, load a simple .txt file in there, saying that there is a new.version and load your updated.exe in there also.
If their app. finds this file, Then to load the little sidekick.app, close it's self, and have the sidekick app do all the leg.work.[/QUOTE]
Agree with codeorder. Get the users to always launch program1. If the shared folder is empty, then program2 is launched, if the folder contains a file, this file overwrites program2, then program2 is launched.
Keep program1 as simple as possible so you don't have to update that as well