# Microsoft RPC/DCOM ### History The Microsoft Active Directory Certificate Services (ADCS), sometimes only called "Microsoft CA", is the Certification Authority software built into Windows Server. The software was originally developed at the end of the last millenium and continued to receive some additions for the next ten to fifteen years. An alternative is Microsoft's SOAP or [SCEP](/enrollment-methods/scep.md), which Microsoft calls Web Enrollment and NDES, respectively. ### Specification and Adoption We have no knowledge of other CA systems implementing this protocol, although Microsoft has published [the specification in Microsoft OpenSpec](https://learn.microsoft.com/en-us/openspecs/windows_protocols/ms-cersod/dd034cb3-99fc-4c10-92c8-1fbeb4788183) in the meantime. On the client-side, Windows has built-in support of the protocol, other platforms are not supported. ### Technology Its main enrollment method is a proprietary protocol based on RPC or DCOM. Autoenrollment also uses this protocol. For autoenrollment to work, you need * a domain-joined device. * Group policy enables autoenrollment, * an Enterprise CA (as opposed to stand-alone) * that enrolls a Certificate Template for which * the user or device has the enrollment and autoenrollment permissions. The default interval to check for autoenrollments is 8 hours, although it can be enforced with `certutil -pulse` or often better `gpupdate -force`. ### Authentication This protocol uses the authentication protocols built into Active Directory, i.e. users and computers authenticate with their AD credentials. --- # Agent Instructions: Querying This Documentation If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question. Perform an HTTP GET request on the current page URL with the `ask` query parameter: ``` GET https://www.x509.wiki/enrollment-methods/microsoft-rpc-dcom.md?ask= ``` The question should be specific, self-contained, and written in natural language. The response will contain a direct answer to the question and relevant excerpts and sources from the documentation. Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.