I still don't understand what you are getting at.
I have never used Hotmail so don't understand how it works.
Basically, Hotmail is a Webmail system that you normally access thro' a browser, using no servers other than the port-80 HTTP one. However it provides custom POP3 & SMTP servers so you can also read and write msgs from/to your Hotmail a/c only
using your favourite email client.
However they can access the IMAP account via Hotmail
How via Hotmail? Do you mean they pull in msgs from your hosted domain into the Hotmail a/c, a la your Q1? In which case they are not using IMAP at all and IMAP has nothing to do with it; Hotmail only uses POP3 access to these "foreign" a/c's. In which case they should cease using Hotmail in this manner and follow my original suggestion of accessing your hosted domain directly from an email client via IMAP.
1999: Freeserve 48K Dial-Up => 2005: Wanadoo 1 Meg BB => 2007: Orange 2 Meg BB => 2008: Orange 8 Meg LLU => 2010: Orange 16 Meg LLU => 2011: Orange 19 Meg WBC
Edited by XRaySpeX (Tue 03-Jan-12 22:55:48)