How can I make SmartScreen Filter trust a self-signed certificate

Question

Microsoft\'s SmartScreen Filter under Windows 8 is a small developer\'s worst nightmare.

While I realize the benefits to end users and the effectiveness at stopping

Answer 1

Using a 90 day trial of Windows 8 from Microsoft, I've been able to verify that my workaround does indeed work. If you want to pay for a code signing certificate once and only once instead of paying annual fees, this method should work for you as well, but I can't make any guarantees. My solution is per-machine, but should be easy to convert to work per-user.

This is my solution:

1. Set up your own certificate infrastructure.
2. Publish copies of your root CA certificate, any intermediate CA certificates issued by your root, and any code signing certificates issued by your intermediate CA's to your website as .cer files.
3. Install an SSL certificate on your website that was issued by your Root CA.
4. Create an installer/downloader application that performs the following tasks:
   • Installs the root CA certificate (from your website, step 2) into the Trusted Root Certification Authorities store for the end user's machine.
   • Disables SmartScreen Filter for the Trusted Sites internet zone by setting HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Internet Settings\Zones\2!2301 to 0.
   • Adds your website to the zone map by adding the registry key(s) HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Internet Settings\ZoneMap\Domains\yourdomain.com\yoursubdomain.
   • Maps your domain to the Trusted Sites zone by creating a DWORD named https with a value of 2 in the key created in the previous step.
5. Purchase a code signing certificate from a member of Microsoft's Trusted Root program, preferably an EV certificate.
   • Before your purchase, make sure the certificate and timestamping scheme used by the CA for your code signing certificate will not result in OID's 1.3.6.1.4.1.311.10.3.13 or 1.3.6.1.4.1.311.10.3.14, as these would make the signature expire when the certificate expires, whether it's timestamped or not.
6. Sign and timestamp your downloader/installer with the certificate purchased in step 5. Verify the absence of lifetime limitations on the signature. If everything is ok, you can put your purchased code signing certificate in a safe place and lock it away.
7. Publish your downloader/installer program to your website. Make it a pre-requisite download for all your products.
8. From this point on, you can use code signing certificates (and other certificates, for that matter) issued by your own internal certificate authorities without SmartScreen Filter being a nuisance.

The worst warning I’ve received using this method so far has been “This type of file could harm your computer.” That's the typical "You're downloading an executable file!" warning. It doesn’t hide the Run option and does not appear for ClickOnce deployments using the bootstrap webpage generated by clicking “Publish” in VS2010.

Thanks for all the comments and links.