Hi!
We do not recommend initiating UWS uninstallation from application's uninstaller, because you can't be sure either that your UWS app was the first one on the system (i.e. that UWS wasn't there before you), or that it is the last one and UWS is not needed anymore. In other words, your attempt to uninstall UWS may disrupt other UWS apps that were installed before or after yours. So we simply do not recommend this for open systems.
If you somehow can ensure that your app is the only one registered with UWS, simply uninstall your app first (and unregister with UWS), and you won't get the warning when you are uninstalling the UWS.
Best regards,
UltiDev Team.
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