This morning I got a call from a user in a remote office who has received an email that purports to contain a "zix secure email" message. It directs him to a page http://zixmessagecenter.com/s/e which has a place for him to enter his google mail account and password in order to decrypt the email.
I did some research (here, among other places) and it seems that zix is a legit company providing secure email, but I have no way to distinguish between what are their real sites and what is phishing. And "zixmessagecenter.com" certainly isn't "zixcorp.com" so I'm not sure that this is really their web site, or some rogue domain that has the artwork of some legit zix pages downloaded and put into their page.
Also, some offhand remarks and links to some stuff from 2014 suggest that at some point google was integrating zix into google mail, so should he have simply seen a legit zix message in cleartext in his google mail?
So how do I tell if this is phishing or not?