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![](data:image/svg+xml, %3Csvg xmlns='http://www.w3.org/2000/svg' height='64' class='font-weight-bold' style='font: 600 30.11764705882353px "SegoeUI", Arial' width='64'%3E%3Ccircle fill='hsl(128, 8%, 22%)' cx='32' cy='32' r='32' /%3E%3Ctext x='50%25' y='55%25' dominant-baseline='middle' text-anchor='middle' fill='%23FFF' %3EA%3C/text%3E%3C/svg%3E)
These ones may help.
https://learn.microsoft.com/en-us/windows/win32/secauthn/key-distribution-center
https://learn.microsoft.com/en-us/windows/security/identity-protection/smart-cards/smart-card-how-smart-card-sign-in-works-in-windows
https://social.technet.microsoft.com/Forums/exchange/en-US/33ad4755-e27e-40aa-bd64-e471da6c0956/do-we-need-directory-email-replication-certificates?forum=winserversecurity
https://learn.microsoft.com/en-us/skypeforbusiness/manage/authentication/assign-a-server-to-server-certificate
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