Recently we migrated to a new domain and the EV was migrated to, now we are having the problem that clients using EV outlook add-in cannot connect to the EV server to retrieve emails using the Add-in.
When I check the EV information in the add-in, I saw that the HTTP connection failed.
By the way, the clients can connect the web url to the server, the problem is just with the add-in.
Do you have some kind of proxy or firewall between the clients and the server? Have you got some of the client trace you can share?