Create upgrade installation

Is there any documentation about how to create upgrade installation?
I tried with version numbers but I get a message about ovewriting files in the location.
Upgrade package shoul avoid such messages.

You can configure the package to always overwrite files in case of an upgrade.

Now, I am getting a message that files are going to be overwritten. How to setup the package to avoid these messages?


Great, Thank’s for your help

In continuation for above;
How to keep the existing old files active & workable in case of upgrading the installation?

Just modify the option above and choose “Skip existing files” or “Only overwrite older existing files”. If you want to go further, you’ll have to use custom actions and file conditional variable to determine whether a given file should be upgraded or not.