When an Enterprise Root CA is installed, it automatically publishes its certificate to the Active Directory store. 3. Automatic Distribution
Microsoft operates its own Root CAs to sign certificates for its vast array of services—Windows Updates, Azure, Office 365, and driver validations.
Understanding Microsoft Root Certificate Authority: Legacy Components and Modern Security
Typically exported or downloaded as a .cer (canonical X.509) file. Encryption Type: RSA-based public key infrastructure.
The Microsoft Root Certificate Authority 2011.cer is a self-signed certificate, which means that it is signed with its own private key. This certificate is valid for a specific period, typically several years, and can be used to issue other certificates.
Modern Windows Updates require the 2011 root certificate to install. If this certificate is missing or corrupted on a machine, Windows Update will fail to verify the payload signatures, resulting in update errors (such as 0x800B0109 - CERT_E_UNTRUSTEDROOT).