This is a security prompt, designed to protect users from unsafe applications that might compromise their machine.
The only way to change what is displayed in that message (and/or prevent it from being displayed altogether) is to obtain a signed certificate for your installer and application, which proves that you're a legitimate vendor with a legitimate executable.
Once you've obtained your certificate from a trusted authority like VeriSign or Comodo, you will need to use signtool.exe
to sign both your application and installer. You can either use SignTool's GUI mode, or integrate it into your build process as a command line application.
Microsoft maintains a help page on code signing here. Another good online resource is here.