I don’t know if I am a bit slow but I spent quite a number of hours searching for a solution for a email client for windows that would connect to my mail-in-a-box server to store contact and calendar information.
Just thought I would share what I found. I did look at many different email clients Thunderbird, The Bat, Outlook, Claws mail, Mailbird…
If the end I came back to old faithful Outlook even though I wanted to try something new.
I found this thing call OpenProtocols Connector http://www.arpdev.com/ it is a freebee but requires registration after 30 days trial. I was able to configure it to talk to my mail-in-a-box server not with the details from the “Contacts & Calendar Synchronization” page in administration of the box but with the details found within the nextcloud calendar page settings in the bottom left hand corner.
They seem to be synchronizing beautifully though it is early days. Just thought I would share what I found as it did take me quite a while to get things to work and I am hoping with will help others out.
If anyone else has got this to work with other mail clients I would be very interested to heard about.
All the Best