The root update package KB931125, when applied might break the authentication process on servers using certificate based authentication: This problem was reported for LDAP over SSL authentication on a Domain Controller, IIS authentication on a webserver and IAS authentication on a Radius server (called Network Policy Server under Windows 2008). The symptoms, patch and workarounds of this issue are explained in this KB. The patch is only available under Windows 2003 and the root update package (KB931125) cannot be uninstalled via WSUS once applied.
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