ClickOnce installation issue after Windows 10 Update

Question

I have strange behaviour. After most recent Windows 10 update all users of my aplication which just installed the update cannot open their clickonce application. Behaviour is when each of them trying to run app, it immediatly closes. It's always the same for each of user who installed last update. Does anyone knows why it happens and how to solve that issue?

Answer 1

We have the same issue with apps that are not signed with a code signing certificate.

After installing the latest version of Windows 10 (1803), ClickOnce just blocks the app, instead of warning the user and letting them open it anyway.

To see if that is your issue, try disabling the SmartScreen in Windows for these kinds of apps:

Under "App & browser control" set the category "Check apps and files" to "Off".

This solution in obviously not very nice but I'm not sure how to fix it other than signing the software.

Answer 2

Another way to get around this problem without disabling SmartScreen is to add the URL of your ClickOnce app to your Trusted Sites in "Internet Options" in Control Panel.

Another option is to sign you ClickOnce app with a CA-issued certificate, but then you have to install the cert in your user's Trusted Publishers certificate store.

https://docs.microsoft.com/en-us/visualstudio/deployment/how-to-add-a-trusted-publisher-to-a-client-computer-for-clickonce-applications