Windows · Storage & Backup
Pool drives for redundancy or capacity
Lets you combine multiple physical drives into a single resilient storage pool, protecting against individual drive failure or expanding usable capacity across devices.
How to open Storage Spaces
- Search for 'Storage Spaces' in the Start menu
- Click 'Create a new pool and storage space'
- Select the drives to include and click 'Create pool'
- Choose a resiliency type and set the size for the new virtual drive
- Click 'Create storage space' to finish
What you should know
- Create a storage pool from two or more physical drives
- Choose resiliency type: Simple, Two-way mirror, or Parity
- Monitor pool health and available capacity
- Add new drives to an existing pool to expand storage
Storage Spaces resiliency protects against drive failure but is not a substitute for a separate backup, since it doesn't protect against accidental deletion, ransomware, or catastrophic loss of the whole PC.
Why it matters
Storage Spaces gives everyday users access to enterprise-style redundant storage without needing a dedicated NAS or RAID controller, which is valuable for anyone storing large media libraries or important files across multiple drives. Choosing the right resiliency type is a meaningful tradeoff between usable capacity and protection against a failed drive, so understanding the options prevents both wasted space and false confidence in data safety. It's particularly relevant for desktop users with several internal or external drives who want a single, expandable, fault-tolerant volume.
Best practices
- Use Two-way mirror or Parity if drive failure protection matters more than raw capacity
- Only pool drives you're comfortable dedicating entirely to the pool, since they can't easily be used individually afterward
- Still maintain a separate backup even with resiliency enabled
- Monitor pool health regularly and replace failing drives promptly
Common problems and fixes
- Pool shows a 'Warning' or 'At risk' health status
- Check for a failed or disconnected drive in the pool and replace it as soon as possible.
- Available capacity is much lower than total drive size
- This is expected with mirror or parity resiliency, which sacrifices raw capacity for redundancy.
- Can't remove a drive from an active pool
- You must first prepare the drive for removal within Storage Spaces to safely migrate its data before disconnecting it.
Tips and tricks
- Label physical drives clearly if using multiple external drives in a pool to simplify future maintenance
- Start with Parity resiliency for the best balance of capacity and protection on three or more drives
Frequently asked questions
Is Storage Spaces the same as RAID?
It's conceptually similar but implemented in software by Windows rather than a hardware RAID controller.
Can I use external USB drives?
Yes, though performance and reliability are generally better with internal or dedicated external enclosures.
What happens if a drive fails in a mirrored pool?
Data remains accessible from the surviving drive copy; you should replace the failed drive to restore full redundancy.
Related settings
- Manage Disks and VolumesProvides a modern interface to view all connected physical disks and their volumes, letting you create, resize, format, or delete partitions without opening the legacy Disk Management console.
- Storage SettingsStorage Settings let you view how much disk space is being used by apps, system files, temporary files, and media. You can free up space automatically using Storage Sense or manually remove unwanted files.
- BackupWindows Backup uses OneDrive to continuously back up your Desktop, Documents, and Pictures folders, along with your list of installed apps, saved Wi-Fi network passwords, and select personalization settings like your theme and wallpaper. It's designed to make restoring your setup on a new PC, or after a reset, far less painful than starting from scratch.
More Storage & Backup guides for Windows
- Storage SenseStorage Sense automatically frees up disk space by deleting temporary files, emptying the Recycle Bin after a set number of days, and clearing out old files from your Downloads folder on a schedule you configure. Once set up, it runs quietly in the background so you don't have to remember to manually clean up disk clutter yourself.
- File HistoryFile History is a legacy Control Panel backup tool that continuously copies versions of files in your libraries, desktop, contacts, and favorites to an external drive or network location. Unlike a single backup snapshot, it keeps multiple versions over time, letting you restore not just a deleted file but an earlier version of one you've since changed.
- OneDrive Sync SettingsConfigures how OneDrive syncs files between this PC and the cloud, including which folders sync, Files On-Demand behavior, and bandwidth limits for uploads and downloads.
- Disk CleanupScans your drive for temporary files, system caches, old Windows update files, and other reclaimable data, then lets you safely delete them to free up disk space.
- Removable Storage AccessManages how Windows handles removable storage devices like USB drives and SD cards, including connection notifications, battery usage behavior, and transfer settings.
- Default Save LocationsLets you set the default drive for new apps, documents, music, pictures, and videos, which is especially useful when a PC has both a small system drive and a larger secondary drive.