Need Help With Lost Partition Recovery

Data Recovery
1

I accidentally lost a partition while trying to resize my drive, and now important files are missing. Disk Management shows the space differently, but I can’t access the partition anymore. I need help with lost partition recovery before I make things worse or overwrite the data.

2

If the partition vanished and you did not write new data to the drive afterward, your odds are still decent. I’ve seen this happen where Windows dropped the partition entry, showed the space as free, and the files were still sitting there untouched.

One catch. SSDs are less forgiving. If this happened on an SSD, TRIM might wipe deleted blocks after some time. I would stop using the drive right away and start recovery fast.

What I’d do:

  1. Stop using the drive.
  2. Confirm whether the partition is gone or only missing a drive letter.
  3. Pull the important files off first.
  4. Try to restore the old partition.
  5. If restoration fails, make a new partition and copy the files back.

First check Disk Management. Sometimes the partition still exists and Windows simply forgot the drive letter. If so, add a letter and you’re done. If the area shows up as Unallocated, the partition was likely deleted.

Step 1: Recover the files

I’d grab the files before trying repairs. Safer that way. I used Disk Drill on Windows 11, and the flow looked the same as Windows 10 from what I saw. It found the missing partition and kept the folders mostly intact, which saved me some sorting later.

Here’s the process:

  1. Install Disk Drill on a different disk, not the damaged one.
  2. Open it and pick the full physical drive where the lost partition used to live.
  3. Hit Search for Lost Data.
  4. If it’s an external drive, it will ask for a scan mode. I picked Universal Scan for normal recovery jobs. Advanced Camera Recovery only makes sense for camera or drone video cards.
  5. Let the scan finish. Don’t cut it short.
  6. If the lost partition appears, open it and look through the folders.
  7. Preview a handful of files. I always test a few photos, docs, or videos before trusting the result.
  8. Select the files you need and click Recover.
  9. Save them onto another drive.

Step 2: Try to bring the partition back

If you want the original partition restored instead of starting over, TestDisk is usually the next thing I’d try.

Steps:

  1. Download TestDisk and launch testdisk_win.
  2. Create the log file.
  3. Choose the physical disk.
  4. Keep the detected partition table unless you already know it’s wrong.
  5. Open Analyse, then run Quick Search.
  6. If it misses the partition, run Deeper Search.
  7. When you find the missing partition, highlight it and choose Write.
  8. Restart the PC.

If it worked, Windows should see the partition again after reboot.

Step 3: Make a new partition if restoration fails

Sometimes TestDisk doesn’t bring it back. Sometimes you don’t care and only want a usable drive again. Fine. At that point I’d make a fresh partition.

  1. Open Disk Management.
  2. Right-click the Unallocated space.
  3. Choose New Simple Volume.
  4. Follow the wizard, assign a drive letter, and do a quick format.
  5. Copy your recovered files back over.

One thing I would not ignore. If the drive clicks, spins up and vanishes, disconnects mid-use, fails to appear reliably, or never shows in Disk Management, stop. That starts looking like hardware trouble, not a partition mistake. Software won’t fix a dying drive. If the files matter, a recovery lab is the safer move.

For a healthy drive with a deleted partition, though, this route usually gives you the best shot. I’ve had it work before, and the big rule was simple. Recover first, repair second.

1 Like
3

If Disk Management shows the space as RAW instead of Unallocated, I’d treat it a bit differently than @mikeappsreviewer suggested. RAW often means the partition entry still points somewhere, but the file system metadata got damaged during the resize. In that case, writing a new partition table too early is risky.

My order would be:

  1. Check SMART first with CrystalDiskInfo. If health looks bad, stop messing with it.
  2. Make a sector-by-sector image of the whole drive with something like HDD Raw Copy Tool or ddrescue.
  3. Work from the image, not the original disk.
  4. Use a file system repair check only after your files are copied out. Do not run chkdsk first. People do this and make a mess fast.
  5. If the partition is NTFS and shows RAW, DMDE is worth a look because it often finds the old volume structure better than general partition tools.

Disk Drill is still a solid pick for lost partition recovery on Windows, esp if you want a simpler UI and file previews before recovery. I’d use it against the cloned image if possible. Safer move.

Also, if this happened during a resize, look for a tiny leftover partition shift. I’ve seen start sectors move by a small amount, and the old data was still there. TestDisk sometimes finds it, sometimes it does not.

Short version, recover files first, but clone first if the drive health is even a little sketchy. And don’t format the space even if Windows keeps nagging you.

If you want a clean search phrase for this mess, use hard drive recovery guide, step by step.

Also found this, watch this quick lost partition recovery walkthrough.

If you post a screenshot of Disk Management, with disk number, RAW vs Unallocated, MBR vs GPT, people here can narrow it down prety fast.

Need Help With Lost Partition Recovery
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4

If Disk Management shows the area as RAW instead of Unallocated, I’d actually be a little more cautious than both @mikeappsreviewer and @viajantedoceu. RAW can mean the partition is still there, but the filesystem got scrambled during the resize, so jumping straight into “fixing” it can make recovery harder.

What I’d check first:

  • Did the partition size stay roughly the same?
  • Is the disk HDD or SSD?
  • Does DiskPart list the partition even if Explorer doesn’t?

Open Command Prompt as admin and run:

diskpart
list disk
select disk X
list partition
list volume

If the volume exists there, don’t recreate anything yet. Also, do not run chkdsk on a RAW volume first. That tool has a bad habit of turning “maybe recoverable” into “now it’s weird and worse.”

My preference is:

  1. Image the drive first if the files are very important.
  2. Scan the whole disk, not just the missing volume.
  3. Recover files to another drive.
  4. Only then mess with partition repair.

Disk Drill is a solid option here because it’s easier to inspect what’s still recoverable before you start writing changes back. That matters more than people think tbh. If folder structure still shows up, that’s a realy good sign.

Also check Event Viewer for disk errors. If you see I/O or controller errors, stop software tinkering and assume hardware trouble.

For extra reading, this thread on how to recover a lost partition and restore missing files is worth a look too.

Post a screenshot of Disk Management and the list partition output. That’ll narrow it down fast.

Need Help With Lost Partition Recovery
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5

I’d add one thing the others only touched lightly: check whether the resize tool changed the partition type GUID/ID or hid the partition, not just deleted it. I’ve seen GPT partitions come back as “Basic Data” gone wrong, or marked hidden/offline, and Windows acts like the volume vanished even though the data is still sitting there.

So before recovery scans, inspect the disk with something that shows partition attributes clearly. MiniTool Partition Wizard, AOMEI, or even a Linux live USB with gdisk/lsblk can reveal if the partition still exists but has the wrong flag. That’s a faster win than deep recovery sometimes.

I slightly disagree with jumping straight to TestDisk writes unless you’re sure about the old boundaries. After a resize, a wrong write can make the next attempt uglier.

About Disk Drill:
Pros: easy previews, good for scanning the whole physical disk, decent at reconstructing folder trees, less intimidating than lower-level tools.
Cons: not the tool I’d trust first for manually correcting partition metadata, deep scans can take ages, best features matter most when you already accepted file recovery over direct partition restoration.

So my order would be:

  1. Verify hidden/offline/type issue
  2. If SSD, pause fast because TRIM is the enemy
  3. Clone if anything looks unstable
  4. Scan the cloned drive with Disk Drill
  5. Only then attempt partition table repair

@viajantedoceu, @yozora, and @mikeappsreviewer are all basically right on the “don’t write to it” part. The missing piece is checking whether the partition is misidentified rather than truly lost. A Disk Management screenshot plus whether this is SSD or HDD would change the advice a lot.