Microsoft’s Advice on Code Signing Best Practices:

Protecting personal and corporate data remains a top concern for consumer and enterprise users of Windows® around the world. Microsoft is committed to implementing new ways to help restrict the spread of malicious software. Digital signatures for software are an important way to ensure robustness and integrity on computer systems. Digital signatures allow the administrator or end user who is installing Windows-based software to know which publisher has provided the software package and whether the package has been tampered with since it was signed.

Earlier versions of Windows used digital signatures to discourage users from installing anonymous ActiveX® controls, download packages, executable files, and drivers from untrusted sources. In Windows Vista®, new features are taking advantage of code-signing technologies.

To read the remainder of this document please download the full document: http://www.microsoft.com/whdc/winlogo/drvsign/best_practices.mspx