Unautorized Access Error ? Add Mailbox Permissions to Accounts

How to fix Unauthorized Access Error of Office 365 Backup & Restore ?

When users are migrating multiple users accounts from Office 365 in bulk, software often shows an error of Unauthorised Access after adding the CSV file for backup or restoration. The error is as following -

Reasons for the Error -

This is mainly because of some setting that needs to done or added to the users is missing. There are Mailbox permissions that needs to be assigned to users/accounts for Admins. You can add thise permissions from Mail Settings to all users accounts in Office 365 Admin account.

Steps to Add Mailbox Permissions

Follow the steps to know how to assign Mailbox permissions to Office 365 user accounts -

Step 1 - Login to Office 365 Account as Admin and then go to Office 365 Admin Center -

Step 2 - From User Management panel or from Acrive Users panel, click on Edit a user -

Step 3 - Once you click on Edit a auser, you will see the list of users as shown below -

Step 4 - Click on user in which you want to add the permission. The box will appear with all the details of the user.

Step 5 - Scroll down below and under Mail Settings option check for mailbox permission. If there are no mailbox permission assigned for admin, you need to add the permission from here -

Step 6 - To Add the permissions, click on Edit button -

Step 7 - Under Mailbox Permission option, click on Edit button to add permissions to Admin for Read and Manage as shown below -

Step 8 - Click on Add Permissions from the following box -

Step 9 - Select the account/admin account to add permission and then click the Save button -