Programmatic access to Exchange Online Mailbox from a .NET application


  • What is the preferred protocol or methodology to programmatically access an Microsoft/Exchange Online mailbox via a .NET application?

    In case you need a little more background on what I'm trying to accomplish...  I have an web based application that supports multiple business clients.  The front end web app is ASP.NET/C# and the backend is SQL 2005.  Each business client has their own customer service email address on Microsoft Online.  When emails come in, the emails need to be loaded into the system so the issues can be worked from a queue and so that emails can be optionally attached to customer records.  I was planning to write a service that periodically retrieves new emails/attachments from each MOS mailbox and stores them in the backend sql database.

    According to one of the FAQs, POP3 and IMAP4 email protocols are not supported.  But, I couldn't find any confirmation whether Exchange Web Services is supported or if there is some other preferred way to programmatically connect to a Microsoft Online Mailbox.  If Exchange Web Services is supported, I thought I'd take a look at the WCF Exchange Server Mail Transport.  If there are no existing APIs (Microsoft or non-Microsoft) for accessing a MOS mailbox, are the MOS email related protocols published somewhere?  I'm not opposed to writing my own code to establish a secure connection, download headers and download messages.  But if something is already available, I don't want to re-invent the wheel.

    Friday, April 16, 2010 6:37 PM


  • Well I have some good news on this.  EWS is definately supported as long as it doesn't require configuring anything on the server.

    Also, I don't know what FAQ you read, but you can request POP be enabled for all of your users (excluding Deskless Workers).

    This sounds a lot like what our Mailbox Migration tool does except, in your case, you are importing them to a CRM or database instead of another mailbox.

    Monday, April 19, 2010 11:00 PM

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