Using Siebel, and web servers are running IIS and Verisign is the key provider. To generate a signed certificate go to the Verisign web site, request a certificate; save it and apply this to IIS
Unable to save the private key from IIS as this option is disabled.
When you export a key from IIS, by default the Export Private Key Option is greyed out. When you export the key you must select: include private key AND you must DISABLE strong encryption of the key file.
See the following article in the Microsoft knowledge base which explains this issue -https://support.microsoft.com/en-us/kb/232154