Requesting certificates via Certificate Enrollment Web Service (CES) fails with error code "ERROR_WINHTTP_TIMEOUT".

Assume the following scenario:

  • You try to request a certificate via a Certificate Enrollment Web Service (CEP) from an Active Directory-integrated certification authority (Enterprise Certification Authority).
  • The operation fails with the following error message:
Certificate Request Processor: The operation timed out 0x80072ee2 (WinHttp: 12002 ERROR_WINHTTP_TIMEOUT)

The Certificate Enrollment Web Services (Certificate Enrollment Policy Web Service, CEP, and Certificate Enrollment Web Service, CES) enable the automatic request and renewal of certificates from a certification authority via a Web-based interface. This eliminates the need to contact the certification authority directly via Remote Procedure Call (RPC). For a more detailed description, see the article "Certificate request basics via Certificate Enrollment Web Services (CEP, CES)„.

Possible causes

Do you know TameMyCerts? TameMyCerts is an add-on for the Microsoft certification authority (Active Directory Certificate Services). It extends the function of the certification authority and enables the Application of regulationsto realize the secure automation of certificate issuance. TameMyCerts is unique in the Microsoft ecosystem and is available under a free license. It can downloaded via GitHub and can be used free of charge.

Possible causes can be:

  • On the CES, the Internet Information Services (IIS) web page is not started.
  • The connection from the client to the CES is blocked by a firewall, which drops the packets without notifying the sender. See also article "Required firewall rules for the Certificate Enrollment Web Service (CES)„.
  • On the CES, no exception for HTTPS connections is set up in the Windows firewall.

Related links:

en_USEnglish