The Importance of Code Signing

Signing your code, especially setup code, is critical for creating a friendly experience for your customers. Windows Vista has the ability to prevent unsigned applications from launching with a full administrator access token. You can check this option, and the other UAC options, by performing these steps:

1. Run gpedit.msc.

2. Confirm consent to run the application.

3. In Group Policy (it might say Local Computer Policy), expand Computer Configuration, then expand Security Settings and Local Policies, and finally expand Security Options.

4. Scroll to the bottom of the list, and you’ll see a series of options prefixed with “User Account Control.”

5. Right-click the security setting that you’d like to view or change.

If the “User Account Control: Only elevate executables that are signed and validated” is enabled, then only digitally signed applications can elevate to administrator. So, if you want your application to operate correctly in locked-down environments, while displaying a more user-friendly user interface, it should be signed with an Authenticode signature.

“Signing and Checking Code with Authenticode” at (MSDN 2002) explains the steps required to digitally sign your code.