Twice in the last 4 days, I have contacted the support and did not receive a reply.
As adding my gmail accounts via pop did not work properly I started forwarding my gmails to my zoho accounts.
For 5 days now the zoho server rejects the forwarded messages.
I am a new zoho user and so far I am not happy at all. My main reason for signing up was the "blacklist" function that turned out to be just a filter.