I'm taking initial steps to start securing a network, and I've come across the fact that a number of machines have Client Certificates for websites installed in the user client certificate store, locally, rather than through AD. These are from a third-party CA, and are business critical.
As a first step, I'm trying to create a list of which certificates each user has installed, so that I can then try to create something more manageable using a GPO or similar, but as they were installed locally, I can't see them in my AD or Certificate Services.
I've been looking at powershell's certificate management cmdlets, but even then, I can only list the current user's certificates, which makes remoting with a domain administrator credential not a valid solution.
How do I go about cataloguing everybody's certificates?