I have a Zoho Mail account with about 5 family email address.  Domain is @edmunds.family

Using Outlook 2016, I am getting sporadic email syncing ... or the latest development, none at all showing in outlook ... they were there, then all just disappeared completely.  However, I can see them on my iphone and on the zoho mail website.

I set up the Exchange Activesync mail in Windows 10 Mail as well, just to check ... and that did a sync, and then all the emails disappeared again as well.  So it doesn't appear to be a client issue, but more an Activesync style issue.

I also have a couple of other domains with Zoho which are working perfectly across multiple clients (the same Outlook 2016 and iphone) and have the same settings.

It has been working well over the last 6 months, but recently the last few weeks, I'm starting to have these sync issues.

My iphone works perfectly, the emails sync in a split second.  The web mail shows all the emails happy and present.