Office 365 Exchange Online - How to access a Shared Mailbox using Thunderbird or other IMAP client RRS feed

  • General discussion

  • I had trouble setting up Thunderbird to use a shared mailbox that was created in Exchange Online (Office 365 Enterprise) but I figured it out and thought I would share the settings.

    Configure Thunderbird IMAP client to access shared mailboxes created in Exchange Online:

    • User Mailbox:
    • Shared Mailbox:

    Settings for IMAP Configuration:

      EMAIL ADDRESS: (shared mailbox)
      PASSWORD: John Smith's Password (user's password)
      IMAP SERVER: (imap server)
      SMTP SERVER: (smtp server)
      USERNAME:\ (user\shared mailbox)

    Once these settings are entered, the application can impersonate the user and access the shared mailbox.


    • Edited by Sean Z Hayes Thursday, April 17, 2014 12:02 AM updated formatting
    • Changed type Sean Z Hayes Thursday, April 17, 2014 12:02 AM This is an answer.
    Wednesday, April 16, 2014 11:57 PM

All replies

  • thank you for sharing!

    In my case, i had to use the shared mailbox alias instead of the address ....

    Friday, August 8, 2014 8:45 PM
  • I tried this, but I keep getting an error message that the login credentials are wrong. I have tried every combination I could think of. Is this not possible anymore?
    Wednesday, August 13, 2014 8:37 PM
  • Hey thanks for sharing this. How exactly did you type the alias?
    e.g.\Info ?

    In my case the shared mailbox is and mine is

    Best regards,


    Tuesday, August 19, 2014 8:52 AM
  • I have the same problems with thunderbird.

    Any tip's


    Thursday, September 4, 2014 7:38 AM

    Exchange Configuration:

      PASSWORD: password

      SHARED MAILBOX:      (could also be, of course)
      SHARED MAILBOX ALIAS: shared-mailbox

      Note: Please make sure to create the UNIQUE alias always with the mailbox, because it creates the user [alias] In this case

    Settings for IMAP Configuration:

      EMAIL ADDRESS: (shared mailbox)


      USERNAME:\shared-mailbox  (user\shared mailbox alias)
      PASSWORD: password (user's password)


      USERNAME:  (users email)
      PASSWORD: password (user's password)


    Tuesday, January 13, 2015 2:54 PM
  • Excellent.  Works great!

    Worth noting that the SMTP server for IMAP is

    Many thanks Samuel.

    Monday, March 23, 2015 10:09 PM
  • Thanks - works perfect :))
    Friday, July 10, 2015 7:06 AM
  • The issue with this is that every mail I sent, it didn't shows on the "sent item" folder on my OWA shared mailbox. Any clue on this?
    Tuesday, February 2, 2016 10:15 AM
  • Brilliant!   - seems to be working for POP3 as well!
    Monday, April 11, 2016 1:43 PM
  • FYI:

    Protocol Server Address Port # Authentication
    POP3 995 SSL
    IMAP4 993 SSL
    SMTP 587 TLS
    Thursday, April 28, 2016 11:41 AM
  • I also have tried every combination of username\shared mailbox logon name and keep getting Authentication failed errors. Anyone have some advice on this?
    Tuesday, August 23, 2016 10:45 PM
  • Thanks it worked!
    Monday, October 3, 2016 4:37 AM
  • in my case didn't work any combination here is my setup:

    EMAIL ADDRESS: (shared mailbox)

    IMAP SERVER: on SSL with 993
    SMTP SERVER: on STARTTLS with 587


    Where alias-name it's what's before @ sign in this case >

    I have no error whatsoever for login, it's accepting my password without any issues, but it doesn't download any message - there is no folder displayed and contents of this shared mailbox it's perfectly visible on  

    In my case all items are in root folder of this shared email there is no subfolder in it like Inbox, Outbox....etc. I'm also getting this message when I click on newly created account in thunderbird.

    I've try already to put in advanced IMAP setting every combination ..... no luck !

    "Subscribe" doesn't list any folder ... indeed I don't have folders under it.

    Thursday, February 23, 2017 12:47 PM
  • For the SMTP Server you can also put your MX record (e.g.

    No login required for this.
    • Edited by jamesAbilia Wednesday, March 8, 2017 10:39 AM
    Wednesday, March 8, 2017 10:38 AM
  • Just messed around with this a bit. In my case it was with the email app on an iphone but I suppose this applies to any client using IMAP/SMTP.

    In my case the customer has a whole bunch of different domains and wants the same first name @ one of their other domains for some users. So far we've made shared mailboxes, set aliases to just the plain name again and then added those into outlook as "name@domain1.tld/name@domain2.tld" but with IMAP you can't include another @ after the / it seems so you're back to having to use some other unique name.

    Something like "name@domain1.tld/name_domain2" as username for outgoing mail server worked. So yeah, make sure to name things descriptively because you never know when that name you thought you just had to set temporarily when creating the mailbox will come back to haunt you.

    Monday, June 5, 2017 8:56 AM
  • Even simpler than this is go to Users > Active users > shared mailbox > Reset password and use it for login in the client.

    You can also use OWA but you need to go directly to the URL:, otherwise, if you go to you will only see the Store app.

    Monday, June 5, 2017 6:15 PM
  • Awesome! Thanks for sharing.

    This may be the answer to the android outlook app not supporting shared mailbox access.

    see victor.onofrei 's sollution at the bottom for an even simpler approach.
    • Edited by Remco Boerma Wednesday, July 19, 2017 12:11 PM redirect to victors sollution.
    Wednesday, July 19, 2017 11:51 AM
  • Best option so far.

    Seems like a workaround to getting shared email boxes as imap only users. Normally you have to pay for those. I don't expect this to stay around for long.

    Wednesday, July 19, 2017 12:10 PM
  • I have a question about the IMAP/Shared Mailbox on O365.

    I have to setup an e-mail address for our HelpDesk Tools, it need to accès and read a mailbox.

    I have created a sharemailbox on Exchange online with a FullAccess permission from a group.

    My question:

    Can i access to this sharemailbox with a simple user (Without any license O365) or to access to a sharemailbox on Cloud a mailbox user is needed ?

    Thank ?


    Thursday, September 28, 2017 11:34 AM
  • Important

    Sorry for the flood, answer is on Microsoft WebSite.


    Important: A user must have an Exchange Online license in order to access a shared mailbox. Shared mailboxes don’t require a separate license. However, if you want to enable In-Place Archive or put an In-Place Hold or a Litigation Hold on a shared mailbox, you must assign an Exchange Online Plan 1 with Exchange Online Archiving or Exchange Online Plan 2 license to the shared mailbox.

    Thursday, September 28, 2017 11:59 AM
  • What worked for me was the following:

    1. Reset the password to the Shared Mailbox from the Office 365 Admin Console
    2. Login once as the account at
    3. Configure the POP account as described above, but using only the shared mailbox email address for the username, e.g., rather than any of the members
    Saturday, February 17, 2018 10:18 PM
  • Really nice idea and IMAP worked directly - just SMTP doesn't seem to work for me.. did you get it running? I only get authentication failed messages...
    Tuesday, July 10, 2018 3:11 PM