We run a mail relay service in a multi tenant deployment for clients. We started doing this because commercially available relay services were silly money when compared to the costs of building one ourselves.
The only thing we have lost in moving to this way of doing things is the ability to retrieve dropped emails. We've been running this service for around 18 months now, and so far haven't had a single complaint about missing emails OR excess Spam, which is pleasing. We have however just been asked by a client how, should the need arise, they could retrieve email. I believe they may have used things like MimeCast or MailControl before, hence the question.
So my question is this:
- If we wanted to retrieve email on their behalf, what settings should we be enabling to keep it and how would we cause this mail to be "released".
- Is there a way users could do this themselves? I'm doubting this one is possible, but this must be a challenge that has come up in the past for other people!