.net: Version numbers for DLL vs EXE?
You'll probably get multiple opinions, but I would say to keep it simple and have the EXEs and the DLLs version stay in sync. I might change my opinion if you really intend to release versions of the DLLs and EXEs independently, but you don't make any mention of that as a requirement. You would take this approach if you are treating some of your files like 3rd-party components (which are released on a different schedule from the main product). But again, if you don't have this requirement, I would say just keep all the file versions in sync.
The convention I have seen work well is to use the first 3 numbers to represent the product version (major/minor etc..) and the 4th part of the version number represents the source control version (so you know exactly which source files the binary came from).
Hope that helps,
John