Sent Messages Received By Others as "Read" Already

Sent Messages Received By Others as "Read" Already

Sending emails to university addresses in the UK and Sweden from my Zoho account means that the emails arrive as "read" already. (This does not happen when I'm sending emails to Gmail, Yahoo, Hotmail, or GMX). I have tried changing the encoding and the priority settings to overcome the problem, but this didn't work.

As I need to correspond with people from academia often, could you please tell me how the problem can be fixed? I don't want them to be missed by not registering in anyone's unread folder.

This is an important point for me.

Thanks.