How do File Versions work with Windows Installer?

Question

I've read about revising the File Version (and Assembly Version) to ensure that an updated file does replace an older/previous file when a WI update installation is carried out, but I don't understand the four-part construction of the File Version ... and my re-versioned files sometimes refuse to transfer to the target computer.
 
For example, a .exe I have recently updated had it's File Version set to 1.0.0.0 (it is resident now in my Program Files (x86)/MyApplication folder) and File Date 23/03/2012, but even now with the File Version set to 2.0.0.10 and a File Date of 24/03/2012 when I use WI to install the new program over the original the 1.0.0.0 file remains in place and the new 2.0.0.10 file does not get installed instead. Why?
 
I read that the protocol is:
 
Major priority: File Version
2nd priority: File date
3rd priority: Language
 
My file language is unchanged, the file date is a function of compile time, but what is the relevance or priority of the four elements of the File Version and how should they be used to drive updating in a secure manner? What should I do to my File Version to make the updated file replace the earlier one? The VS Help Viewer says "Highest Version Wins—All other things being equal, the file with the highest version wins, even if the file on the computer has the highest version." So - referring to the four element File Version string, what is higher or lower than what?
 
Thanks,
Nick B

Answer 1

Hi Nick,

Welcome to the MSDN forum.

Did you set DetectNewerInstalledVersion and RemovePreviousVersions to true? I found a similar question at here.

If I misunderstood anything, please feel free and let me know.

Best regards,

---

Shanks Zen
MSDN Community Support | Feedback to us

Answer 2

Shanks,

I have found my mistake - I was simply not careful enough targeting the right build folder when inserting links into my File System. Lesson learned ... 

Can I take it then that a "higher" file version is simply detected by reading the four number elements from left to right, with cascaded natural / numeric superiority for precedence?

Thanks,
Nick