Error 107 ERR_SSL_PROTOCOL_ERROR

Needing to apply SSL to an existing website (on my Windows Server 2003 development machine) I recently opened the properties on the website (under IIS, Web Sites), clicked Directory Security and Server Certificate and chose to apply/replace the certificate from an existing site/certificate.

This did not have the required effect, when requesting the page in the browser:

• Using HTTP://
  The page must be viewed over a secure channel
• Using HTTPS://
  Error 107 (net::ERR_SSL_PROTOCOL_ERROR): Unknown error IIS
• And occasionally
  Bad Request (Invalid Hostname)

Essentially, this is because I was trying to reuse an existing certificate on a web site that had a different name. The solution is basically to replace the certificate with a valid certificate either from a trusted Certificate Authority (CA) or to use the SelfSSL.exe.

All of this is documented here, the first link being how to use the SelfSSL to get the job done on a development box:

• http://springboardpillow.blogspot.com/2009/03/creating-certificate-in-iis.html
• Securing a web service with SSL: http://msdn.microsoft.com/en-us/library/aa302409.aspx
• Configuring your web server to use SSL: http://support.microsoft.com/kb/324069
• Securing XML web services created using ASP.NET: http://msdn.microsoft.com/en-us/library/w67h0dw7(VS.71).aspx
• Renewing a wildcard SSL certificate in IIS 6: http://stackoverflow.com/questions/1389941/renewing-a-wildcard-ssl-certificate-in-iis-6-1024-to-2048-bit
• Easily secure custom web services with .NET: http://articles.techrepublic.com.com/5100-10878_11-5779491.html
• HTTPS Web Request and Web Response: http://www.tech-archive.net/Archive/DotNet/microsoft.public.dotnet.languages.csharp/2005-06/msg00038.html

It is important to note that when applying SSL certificates, especially via SelfSSL, that you open the site's Properties dialog:

• Click Web Site tab
• Click Advanced button
• Under Multiple SSL identifies for this Web site select the site's IP row
• Click Edit button
• From the IP address drop down menu select the IP address of that site
• Click Ok, Ok, Ok

This associates the SSL certificate with the site's IP and ensures that there are no conflicts. Click the Help button in this window for more information.