Zoho Mail Error: Reason:Connection reset.

Zoho Mail Error: Reason:Connection reset.

I have recently configured an email address hosted by MS Office Live as Pop3 in Z Mail.  The Pop3 settings are the same as for Hotmail, except that the OUT port can (I believe) be either 25 or 587, and the email address is for my domain rather than hotmail.com.  It works intermittently, but occasionally stops.

For example today I got the error message on sending "Reason:Connection reset. Your Mail has been placed in outbox for retrying".  I then changed the OUT port from 587 to 25 and it went OK.  I had a different error message yesterday and when I changed it from 25 to 587 it seemed to fix the problem (until today).

Does anyone have any suggestions on what might be wrong?  I am finding more customers using Office Live with their own domains, so I am sure this problem will recurr.

John Haigh, Ascent Business  - UK-based Zoho solution partner.