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So we have a website. I do all my emails using Microsoft Hosted Exchange. Some other people in the company use the email accounts of our website provider.

Now what I would like to do is to have a company email account ( but actually use that Microsoft service (@microsoft…com). This should not disrupt the email accounts of my coworkers, though.

My website provider tells me I need to change the MX record. Microsoft says I need to change my CNAME. Frankly, I don't really know what either of those really mean but there is some sort of configuration interface that will let me add and delete CNAME or MX records.

So my question is: Is it even possible to have two different mail providers for my domain?
What do I have to do to get this working? (I know this is kind of a fuzzy question. I will gladly provide more detail if that helps)

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If you're not familiar with MX and CNAME records, then I strongly suggest that you don't experiment with this stuff. You risk disabling the e-mail service for yourself and all your coworkers! They would probably not thank you for it. – Torben Gundtofte-Bruun Nov 12 '10 at 22:25

3 Answers 3

up vote 2 down vote accepted

No, there's no way to direct to a different provider than


  • Set up some forwarding. (Like from your website provider to the hosted Exchange provider, after the message has first been received by the former.)

  • Use subdomains. (And then set up different DNS records, to make refer to a different email provider, to have email for be handled differently from and Not too nice.)

(An email sender will look up the so-called MX records of your domain. Though one can define multiple records for fallback servers, those will only be used if the primary server does not respond, not if the primary server does not know your email address. Hence: email senders will always try to deliver all email for some domain to the same provider, or will return the message if that fails.)

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No, you can have only one mail provider per domain. But there are workaround, if you know what you're doing. I've had an arrangement for a while that worked well, but it was carefully done.

The story was a migration from one hosting/mail provider to another. It involved setting up everything (mailboxes, addresses, groups, etc.) in the new place except for the MX records, so it could receive everything. But it didn't receive anything because the MX was still pointing to the old system. Then the old system was changed so that every mailbox forwarded every message to the new system. Users could then check their mail on either system. Eventually all the users were checking mail in the new system, and the MX was finally switched to the new system, and only from then on all mails went directly to the new system - no longer passed through the old system.

It required careful planning and even more careful setup of the new system. And even so, there were some minor problems because when mails were sent from the new system but the MX was still pointing to the old system, some recipients rejected the messages because they looked spammy.

Summary: Don't mess with this unless you really know what you're doing! If you mess up, it can be really hard to fix, and you are guaranteed to have lost an unknown number of emails to your organisation!

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So: it's not possible to have multiple providers simultaneously for the exact same domain, right? (The above merely describes what happens when changing providers, because the DNS servers and the cached results are not updated instantaneously.) – Arjan Nov 13 '10 at 12:35
Correct; there can be only one MX record for a domain, and that will decide which provider handles the e-mail. The answer above describes a workaround. I've added this to the answer now. – Torben Gundtofte-Bruun Nov 14 '10 at 10:05
Now I'm even more confused... How is this a workaround? If I am correct, then the question is about routing to some server, and the another? (To set up forwarding for, I'd say no messing with MX is needed. As an aside: I also think it's odd that MX records triggered spam filters. Weren't that SPF records, or something like that?) – Arjan Nov 14 '10 at 10:17
I left out the dirty details in my answer. The workaround routed everything to the old MX where there were rules to forward mails to a different MX on a temporary domain. Once everybody updated their mail clients, the old MX was pointed to the new server. So there were two different MX's for a while! – Torben Gundtofte-Bruun Nov 14 '10 at 10:31
...but that is not what this question is about? – Arjan Nov 14 '10 at 10:43

I had to do something like this once:
I haven't done it with hosted exchange, so this might not be pertinent any more.

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