Okay — I’ll walk you through safely removing C:\Windows.old. Do this only once you’re sure you no longer need any files from the previous installation (profiles, custom app files, installers, etc.). I’ll give the safest, recommended GUI method first (Disk Cleanup / System Files) and then an explicit PowerShell method you can use if you prefer. I’ll also show how to verify everything and how to recover if something goes wrong.
Before you start — important reminders
- Deleting C:\Windows.old is permanent (it contains the previous Windows installation). After deletion you cannot roll back to the old install.
- You already have restore points and repaired the system earlier — good. If you want extra safety, create a fresh system image (Macrium Reflect or other) before deleting. If you don’t want a full image, at least create a restore point (may be subject to the 24‑hour throttle).
- Close all programs and make sure no installers or processes are using files in C:\Windows.old.
Recommended (safe) method — Disk Cleanup (removes previous Windows install safely)
1) Open Disk Cleanup as administrator:
- Press Start, type Disk Cleanup, right‑click Disk Cleanup and choose Run as administrator.
- Or press Win, type cleanmgr, then right‑click and Run as administrator.
2) Choose drive C: when prompted.
3) Click “Clean up system files” (you’ll be asked C: again — select it).
4) Wait while it scans. In the list of items to remove, look for:
- Previous Windows installation(s) (this is Windows.old)
- Temporary Windows installation files (optional)
- Temporary files, and other large items you want to remove
5) Check “Previous Windows installation(s)” and any other items you want removed, then click OK → Delete Files.
6) Confirm and wait — this can take some time. When finished Windows.old will be removed and space reclaimed. A restart is not usually required but may be prompted.
Alternative GUI: Storage Settings
- Settings → System → Storage → Temporary files → wait to scan → check “Previous version of Windows” (or “Previous Windows installation(s)”) → Remove files.
Command-line / PowerShell method (faster, but be careful)
If you prefer PowerShell and you’re certain you want to delete it now, run this as Administrator:
Test-Path C:\Windows.old
If True and you want to delete:
Take ownership (if needed)
takeown /F "C:\Windows.old" /R /D Y
Grant Administrators full control (if needed)
icacls "C:\Windows.old" /grant Administrators:F /T
Remove the folder (this is permanent)
Remove-Item "C:\Windows.old" -Recurse -Force
Notes:
- The takeown/icacls lines are only necessary if PowerShell complains about permissions.
- Remove-Item can take many minutes depending on size. Don’t interrupt it.
Verify the deletion
- After completion run:
Test-Path C:\Windows.old
It should return False.
If Disk Cleanup / Remove‑Item can’t remove a file
- Reboot into Safe Mode and retry Disk Cleanup or Remove‑Item, or run the disk cleanup approach from Windows Recovery/PE if needed. But you likely won’t need this.
Finally — create a final restore point (recommended)
After the deletion and once you confirm everything is working, create a fresh restore point or a disk image so you have a clean baseline.
Quick Restore Point (Admin PowerShell):
Enable-ComputerRestore -Drive "C:\"
Checkpoint-Computer -Description "Post-AdobeInstall Baseline" -RestorePointType "MODIFY_SETTINGS"
(If the 24‑hour throttle prevents immediate creation, you can use the image approach instead.)
Would you like me to:
- Walk you through Disk Cleanup step‑by‑step now (I’ll wait while you run it), or
- Give the exact PowerShell Remove-Item commands and wait while you run them, or
- Wait while you create a disk image first and then delete Windows.old?
Tell me which method you want and I’ll wait while you run it and confirm the result.