C Drive Filling Up Automatically Windows 11 Fix [2026]

Quick Answer: C drive fills from Windows Update cache, temp files, and hibernation file. Run Disk Cleanup as Administrator and check WinSxS component store bloat.

Symptoms

C drive losing space daily
"Low disk space" warnings
No large files visible
Space disappears after updates

Root Cause

Windows Update cache, temp files, pagefile, hibernation file, or system restore points.

Fix

Method 1: Disk Cleanup

Disk Cleanup → Clean up system files
Check: Windows Update Cleanup, Temporary files, Recycle Bin

Method 2: Check Large Folders

Get-ChildItem C:\ -Recurse -ErrorAction SilentlyContinue | Sort-Object Length -Descending | Select-Object -First 20

Method 3: Reduce Hibernation

powercfg /hibernate off

Method 4: Move Pagefile

System Properties → Advanced → Performance → Virtual Memory → Move to D: drive

How Againly Helps

Againly can inspect the relevant local evidence and propose a fix plan for review.

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Related: 100% Disk Usage Fix

Evidence-led support

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