DLL missing Certificeat Manager

[Chuck]

..Hello,
When I attempted to register my ssl certificate, I could not find
Certificates in the mmc Add Remove Snap In window. During investigation I
found that CertMgr.msc was in my system32 folder, but CertMgr.dll was not.
In fact it doesn't appear to be on the server when doing a file search.
Where can I go (and trust) to find this file so I can download it?

Thanks!
Chuck