OneDrive isn’t just used for documents and photos. Microsoft saves a lot of related files in secret, hidden folders taking up the space customers pay for and preventing proper backup. Let’s look at the messy mix of things hidden in OneDrive and other Microsoft online locations.
You can see what’s saved on your OneDrive storage on the web site, click the Settings ‘cog’ then Options | Manage Storage.
In this example, most of the space is taken with customer files but there’s other Microsoft products that take up OneDrive space in hidden folders. Loop, Designer and especially any attachments to Outlook mail.
Why this matters
There are two main reasons why hidden folders on OneDrive are a problem for Microsoft’s customers.
Uses up the space you’ve paid for
Many of the hidden folders will usually take up little space. For example Loop components would rarely get large. Heavy use of Designer could accumulate a lot of images and designs.
On the other hand, email “Outlook” attachments can take up a lot of space.
All these hidden uses of OneDrive leave less space for the customers files.
Can’t backup
Hidden OneDrive folders can’t be copied or backed up. It’s important to have everything backed up that’s saved in cloud storage. Despite all the promises, no form of storage is 100% reliable.
OneDrive hidden folders are only saved in one place and they rely on Microsoft’s systems to keep any safety copies.
Personal backups are important if Microsoft’s automated systems decide to block access to OneDrive. Any suspension of service by Microsoft doesn’t just prevent use of documents, it can also affect services like Loop, Designer and Forms.
Bitlocker
We’ll start with some important mythbusting,
Despite what you might have read, Bitlocker Recovery Keys are NOT automatically saved on OneDrive.
Those details are linked to a Microsoft account (you can see them at https://aka.ms/myrecoverykey ). If Microsoft blocks access to OneDrive storage that should not prevent access Bitlocker recovery codes.
That said, it’s a very good idea to save Bitlocker Recovery codes in several different places and not just online.
Bitlocker Recovery Keys can be (and should be) saved to separate text files and those files could be copied to OneDrive.
Windows Backup / Known Folder Move
The Windows Backup (officially called Known Folder Move) is really copying and syncing folders from the local computer to OneDrive.
All those folders are visible in OneDrive but can take up a lot of space.
Outlook attachments
Microsoft hosted email including Outlook.com and Hotmail has changed where email attachments are saved.
Attachments are now saved as part of the OneDrive quota though in a hidden area. The only way to access attachments is still via the mailbox.
You might think this is a cynical change by Microsoft to use up more of the OneDrive space and you’d be right.
Designer
Originally, all Designer related files were saved at the customers /Apps/Designer folder on OneDrive. That was really convenient for accessing images, copying designs and uploading many fonts. Some files are still saved in that location.
It was so useful that Microsoft, naturally, had to stop that. Now Designer files are in some hidden part of the customers OneDrive storage.
Loop, Forms and Lists
All three of these Microsoft services save their data in the users OneDrive account or SharePoint for organizations.
OneNote
OneNote Notebooks are saved to OneDrive by default. Most likely in the visible Documents/OneNote folder.
What else?
Microsoft is (deliberately?) vague about what’s saved in OneDrive vs the Microsoft account. Anything saved in OneDrive counts against the customers quota (5GB for free, 1TB for Microsoft 365 plans).
For example, Windows Backup can also save Settings and Credentials but it’s not clear if those details are saved in a hidden part of OneDrive or linked to the Microsoft account.
Teams meetings recordings and chat file attachments can be saved in OneDrive.
Xbox Game Pass can save game details to a hidden part of OneDrive.
Why have my files moved to OneDrive?
Protect Your Files from OneDrive: Beware Microsoft Account Lockouts
