How To - Office365 email shared inbox in Outlook for Android & Thunderbird

Easy access to and timely notifications from shared mailboxes are important especially when you are responsible for keeping things running. And responsible I am, as I am currently the IT guy at a newly spawned startup running a platform for monitoring and management of off-grid energy assets called AMMP. As a non-MS user I often run into trouble when I have to deal with MS related stuff due to lack of support for Linux OS.

Today's challenge: Viewing a shared Office365 email inbox via delegation (using your personal credentials) if you are not using the MS Office Desktop Outlook Client. Most often that is the case with devices running Linux or Android.

So how to view a shared Ofice365 mailbox if you don't have Outlook for Desktop?
As it turns out the solution is rather straightforward.
Here are a few options that I have managed to get working and hopefully will spare you the research time I've invested so far.

1. Web client - open another mailbox - outlook.office.com
   
   1. Open your email in the browser
   2. In the upper right corner click your profile icon
   3. Select Open another mailbox...
   4. Type the name in the pop-up
   5. A second window/tab opens for you with the respective inbox
2. Web client - add shared folder to your mailbox
   
   1. Open your email in the browser
   2. In the explorer panel on the left under Folders click on More
   3. Right click your name
   4. Select Add shared folder...
   5. Enter the name of the shared email in the pop-up
   6. Now you can view the contents in the same window/tab alongside your emails. (They don't mix with your inbox though)
      
3. Thunderbird - add second shared mailbox
   
   1. Click Add new email account
   2. Enter the shared email that you want to add, e.g. team@company.com
   3. Don't enter password
   4. Click next. Thunderbird should auto detect some settings.
   5. Select IMAP
   6. Click on manual configuration
   7. Under username for IMAP enter your.email@company.com/team
      Notice the extra slash plus the name of the shared email
   8. Under username for SMTP enter just your.email@company.com 
   9. Enter your account password (above)
   10. Click Finish
       NB: If you have more than one domain name under the same office365 account and you have emails with the same name (the part before the @ symbol) for a particular shared inbox, e.g. team@company.com and team@company2.com then you may run into issues related to name conflict. In such a case you (or an administrator) could create an alias for the shared email that you need to access and choose a name that is unique within that pool of email addresses. For example, you could create team.company@company.com and team.company2@company2.com and then use your.email@company.com/team.company to access team@company.com
       
4. Android - Official MS Outlook App
   Contrary to what Microsoft will have you believe their Android Outlook App does support shared mailboxes once you get past all the hurdles of custom configuration
   
   Here is how it goes:
   1. In the App tap to add a new email account.
   2. Enter the shared email address, e.g. team@company.com. It should detect that it as an office365 email and ask you for a password. However, no password is associated with that account, otherwise you'd be able to enter it and sign in. (And you'd also be charged licensing fee)
   3. Don't enter password but press back. It should take you to another screen and ask you to choose an account type.
   4. Choose Advanced -> IMAP account type.
   5. Tap Advanced settings to extend configuration form
   6. You need to enter the following details:
       * (Incoming Email Server)
          IMAP Host Name: imap-mail.outlook.com:993
          IMAP Username: your.email@company.com/team
          IMAP Password: *****your*password*
   
       * (Outgoing Email Server)
          SMTP Host Name: smtp-mail.outlook.com:587
          SMTP Username: your.email@company.com
          SMTP Password: ****your*password*
   
       The IMAP Username is your email address, with a slash at the end and the name of the other mailbox that you want to add.
       The SMTP Username is just your email address.
       The password in both cases is your password, not the one for the shared mailbox (which shouldn't exist).
       For the host names apparently you have more than one option and you may have organization specific ones. But what is important is that you can include a port number at the end of the domain and you should if one is specified.
   
       A couple of options to try are:
       *  Thunderbird auto-detected:
           IMAP:  imap-mail.outlook.com:993
           SMTP: smtp-mail.outlook.com:587
       * Suggested by Microsoft:
           IMAP: outlook.office365.com:993
           SMTP: smtp.office365.com:587
   
       (SSL/TLS options are not available in the app as of this writing)
   
   
   7. Press next/finish and you should have access to the newly added mailbox