When Integrated Apps is turned on, users in your organization can allow third-party apps to access their Office 365 information. For example, when someone uses a third-party app, that app might ask for permission to access their calendar and to edit files that are in a OneDrive folder.
In order to access the feature of Outlook.com Backup tool , you need to Enable Less Secure Apps from your Microsoft Live Mail Account. Below is the complete procedure for the same.
Step 1: Go to Admin Portal of your Office 365 account and click on Settings.
Step 2: Select Service & ad-ins from setting. On thr right side of this menu select Integrated Apps
Step 3: Now Enable Less secure apps authentication and click Save.