Code signing certificate not available to sign macros
Solution 1:
I think I found where the issue was coming from.
The server I have is a Windows Server 2008 Standard, and from Microsoft's documentation it only supports version 1 of certificates.
I can create a custom certificate template for code signing, but I can't make this template available to my domain users because custom templates version is either 2 or 3.
So I can create a code signing certificate template, but my users cannot request this type of certificate as long as I don't have a Windows 2008 R2 or Enterprise or Datacenter edition that has the CA role.
The first certificate created could not be used as code signing.