I have a GoDaddy SSL certificate installed on my 2007 Exchange server. It has the external and internal domain names, and the autodiscover for both. Today the internal clients started popping up a message that the certificate was expired, and offering a login for the Exchange server. Externally, phones are syncing using SSL, and if I go to Outlook Web Access I can see that the certificate for it is valid. Outlook Web Access with https is even working internally. In the server's event log there is a message that a certificate is expiring or expired, and gives the thumbprint. That thumbprint corresponds to the GoDaddy certificate that was valid from Sept. 2010 - Sept. 2011. There is a new certificate which is identical which is valid from Sept. 2011 - Sept. 2012. In Exchange, the newer certificate is applied to services POP, IMAP ,SMTP and Web. The older one is applied to POP and IMAP (which aren't being used). I am totally confused as to why this certificate, which expired months ago, is suddenly causing these problems, and apparently only for the internal autodiscover portion of the certificate. And how do I fix it? Is it as simple as removing that certificate? I don't think so because for whatever reason the system thinks it needs this certificate for internal autodiscover. Please help!!!