I'm not SURE if InstallShield has this capablity or not, but it is an extremely powerful and versatile product. That said... it's not easy. It's like learning a whole new programming language. And of course you always need to use it at the 11th hour when your program is 'done' and all you want to do is SHIP it! :)

Also check into Installshield Lite. I've heard that it has a lot of the same functionality, but it a lot easier to use.

>>I believe InstallShield can also create 'delta' patches, where only the changed code is actually distributed to update a client's software.

HTH -