Our various servers, supporting OpenLabyrinth and the OLab education research platform, had some hiccups for a while, which resulted in our support of https and SSL being rather patchy.
Most people will find these days that many web browsers have conniptions about visiting unsecured sites, so many of you were getting dire warning about the site being insecure or have an invalid security certificate.
I think we have all that fixed now and there should be no more warnings.
Just to reassure you, there was no actual compromise of our sites and the data remains secure.