Below I have created a quick guide to show you how to gain access to a user’s OneDrive within your organisation. This video is for SharePoint administrators and you will need to be at least a SharePoint admin in Office 365 to carry out these steps.
A OneDrive site is effectively a SharePoint site collection with a document library. When a OneDrive is created by the user in Office 365, it grants the user site collection admin rights. It doesn’t add any other administrators or groups to the permissions. You can do this manually using the steps shown in the video below or you could create a script to apply permissions to all of your OneDrive sites using the PowerShell Client Object Model.