I get a sec_error_bad_signature when trying to open the following URL: https://mfacilities.betavine.net Using an SSL validation tool the certificate chain seems OK: http://www.networking4all.com/en/support/tools/site+check/report/?fqdn=mfacilities.betavine.net&protocol=https I understand that the Certificate Verification procedure used by Firefox changed in version 31 (see https://wiki.mozilla.org/SecurityEngineering/Certificate_Verification). A workaround was possible to revert to the old procedure but that has now been removed in version 33. Any advice on how to diagnose the problem or work around it? The site loads OK with Safari, Chrome and IE. Robin Summerhill Vodafone UK