If an update installer is not the same than a regular installer, in which way are they different?
Upgrade installers do not create a new uninstaller. Instead, the new installed files will be appended to the existing uninstaller, and persistent variables and parameters from the upgrade installer will be as well registered in the exiting uninstaller.
Additionally, on Windows an upgrade installer will not create a new entry on the ARP (Add/Remove Programs) Menu. Instead, it will update the "version" field for the existing entry of the application. Also, it will not create a new entry into the Start Menu.
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