Link to home
Create AccountLog in
Avatar of roy_batty
roy_battyFlag for United Kingdom of Great Britain and Northern Ireland

asked on

Multiple external users need access to Office 365 mailbox

I need to create a new mailbox in our office 365 tenant. I then want to give access to this mail to external people. Ideally they will be able to access this mailbox using outlook. I can provide them with the login details etc. We also have multi factor authentication enabled on all accounts in our tenant. How do I best deal with sharing this mailbox among multiple external users?      

Avatar of Ross McCandless
Ross McCandless
Flag of United Kingdom of Great Britain and Northern Ireland image

This isn't possible as part of delegation:

  • External users: You can't give people outside your business (such as people with a Gmail account) access to your shared mailbox. If you want to do this, consider creating a group for Outlook instead. To learn more, see Create a Microsoft 365 group in the admin center.

If you create a new user mailbox and provide them with the credentials then they can add to their outlook profile or use via OWA

If it is the same mailbox for multiple external users then you will likely hit problems with MFA as well as cyber risk

Sharing credentials is against the licensing terms though, so avoid doing that. Plus, you will lose all accountability as to any action peformed by this user/mailbox.

Avatar of roy_batty


So really what we are saying here is that each person that needs access to this mailbox needs to have their own paid up licence and then I create a shared mailbox and share it to them. Treat them like member of staff. That solves the MFA issue too.

So if I do this can I prevent the new users from sending/receiving emails via their own mailbox ?

Avatar of Vasil Michev (MVP)
Vasil Michev (MVP)
Flag of Bulgaria image

Link to home
Create an account to see this answer
Signing up is free. No credit card required.
Create Account