This article was written about products for which Microsoft no longer offers support. Therefore, this article is offered "as is" and will no longer be updated.
When you connect to an Internet Information Services (IIS) 5.0 computer, you may receive the following error message:
HTTP 403.17 - Forbidden: Client certificate has expired or is not yet valid The page requires a valid client certificate
The page you are trying to view requires the use of a valid client certificate. Your client certificate has expired or is not yet valid. The client certificate is used for identifying you as a valid user of the resource.
Generic 403 errors are returned when access to content has been forbidden. The server is refusing to fulfill the request for content. This is generally not related to NTFS permissions.
To resolve this, do the following:
Check the Effective Date on the client certificate.
Ensure that the certificate is valid.
Check the Expiration Date on the client certificate.
Ensure that the certificate has not expired.
Verify that the Certificate Authority has not expired your certificate.
Request a new certificate from the Certificate Authority.
For additional information on requesting a new certificate, click the article number below to view the article in the Microsoft Knowledge Base: