The warning window that you are seeing is likely the result of Windows SmartScreen, a security feature that helps protect users from downloading and running malicious software.
To remove this warning, you can try signing your ClickOnce application with a trusted code signing certificate. This will verify your identity as a trusted developer and help users to trust your application.
Here are the steps to sign your ClickOnce application:
- Obtain a code signing certificate from a trusted certificate authority (CA).
- In Visual Studio, go to the project properties and select the "Signing" tab.
- Check the "Sign the ClickOnce manifests" option.
- Select your code signing certificate from the "Choose a strong name key file" dropdown.
- Click "OK" to save the changes.
- Rebuild your application and publish it again.
After you have signed your application, you may need to ask your clients to trust the certificate. This can usually be done by right-clicking on the executable file and selecting "Properties", then going to the "Digital Signatures" tab and clicking "Details", followed by "View Certificate" and then "Install Certificate".
Note that the exact steps may vary slightly depending on your version of Visual Studio and the certificate authority you use to obtain your code signing certificate.
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