As of about 10:00 PM EST last night none of our certificates that we bought from Dynadot are validating. After looking at the logs it appears as though this is caused by browsers not being able to access the certificate store at http://secure2.alphassl.com/cacert/gsalphasha2g2r1.crt
I tried accessing this URL from multiple browsers and multiple locations and it appears to be down. Does anyone know when this will be fixed?