How to add a shared mailbox on o365 without a password

There are two options.

Option 1:

Use the BULK ADD option.

 

Option 2:

Authenticating a shared ‘unlicensed mailbox’

Step1. Logon to Microsoft Office 365 as your tenant admin to https://portal.office.com/

 

Step2. Navigate to the ‘Users’ section. https://admin.microsoft.com/AdminPortal/Home#/users

 

Step3. Select the shared ‘unlicensed’ mailbox from the list.

 

Step4. Press re-set password

 

Step5. Specify a password.

 

Step6. Leaving the Office 365 portal in a new tab open up TimeToReplyand navigate to the agents page: https://portal.timetoreply.com/tools/agents

 

Step7. Press Add Agent/Add Another

 

Step8. Give the mailbox a friendly display name, specify the mailbox email address and Office 365 as the service type, and press send invite.

 

Step9. Navigate to the agents / mailboxes section under tools https://portal.timetoreply.com/tools/agents

 

Step10. Press view current authentication link

 

 

Step11. Visit this link and sign in as the shared mailbox using the details you created earlier.