A client has a OWA site and the SSL certificate for it is displaying the correct date when the site is viewed internally. However externally it displays a certificate that expired a year ago. The certificate has been removed from the server but it still displays it. IIS shows that the correct certificate is set in the bindings. Even more bizarrely is that it does not warn of an unsecured certificate when attempting to view the site.
EDIT: Turns out I had added an exception in Firefox to ignore the unsecured certificate