When you try to install a certificate from a PKCS#7 file by using Internet Information Services (IIS) 7.0 Manager, you may receive one of the following error messages:
Error message 1
Cannot find the certificate request associated with this certificate file. A certificate request must be completed on the computer where it was created.
Error message 2
There was an error while performing this operation
Details: CertEnroll::CX509Enrollment::p_InstallResponse: ASN1 bad tag value met. 0x8009310b (ASN:276)
Details: CertEnroll::CX509Enrollment::p_InstallResponse: ASN1 bad tag value met. 0x8009310b (ASN:276)
This issue occurs because IIS Manager performs a lookup operation to look for a friendly name of the certificate during the installation. However, the code that performs this lookup operation misses this specific case, and it does not know how to retrieve the friendly name of a certificate in a PKCS#7 file. Therefore, the lookup operation fails, and you receive the error message. This issue is scheduled to be resolved in the next Windows Server 2008 service pack.
Note: The certificate is installed correctly despite the error message
Thanks to Karsten Palmvig who pointed me in the right direction in this post: http://blogs.technet.com/kpalmvig/archive/2009/09/22/troubleshoot-cannot-complete-certificate-request-in-iis-7.aspx
Original Technet article: http://support.microsoft.com/default.aspx/kb/959216
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