There’s a moment every Windows user dreads — opening File Explorer and seeing the C drive bar turn red. It’s not just a color; it’s a warning. A red C drive means your system is running low on space, Windows is struggling to breathe, and performance is about to drop.
Your laptop may start lagging. Programs may freeze. And in the worst case, Windows can crash because it has no room left to operate.
In this guide, we’ll walk through a step-by-step, deep-cleaning process that can easily free 100–150GB of space — all without installing any third-party software. These steps are safe, built into Windows, and incredibly effective for finding the hidden files that silently eat up your SSD.
Let’s begin.
🚨 Why Your C Drive Turns Red — And Why It’s Dangerous
Before we start clearing space, it’s important to understand why this happens.
The C drive contains:
- Windows system files
- Installed applications
- Drivers
- Temporary data
- Cache folders
- Hidden app storage
When the C drive becomes full:
- Windows cannot create temporary files
- Background services fail
- Programs lag or crash
- Updates stop installing
- SSD speed drops dramatically
Even if you clean temp files regularly, Windows and apps often keep hidden data that grows silently.
But the good news is: with the right cleaning steps, you can recover a huge amount of space.
🧹 Step 1: Perform the Basic Windows Cleanup
Let’s begin with simple built-in cleanup steps.
1️⃣ Empty the Recycle Bin
If you haven’t emptied it in a while, this alone may free several GB.
2️⃣ Delete Temp Files
Press Windows + R, type:
temp
Delete everything inside. Skip the files that can’t be removed.
Now again press Windows + R, type:
%temp%
Delete everything here too. These are safe system caches and temporary files.
🔍 Step 2: Identify Gigantic Files in Your C Drive
Instead of checking folders manually, use Windows search filters to find big files instantly.
1️⃣ Find files larger than 5GB
Open File Explorer → search bar → type:
size:>5GB
Delete the files you don’t need.
2️⃣ Find files larger than 1GB
Search:
size:>1GB
Check each file before deleting.
Every hidden ISO, installer, or leftover export you forgot about will show up here.
⚙️ Step 3: Check Windows Storage Breakdown
Open:
Settings → System → Storage
Here Windows shows which areas are using the most space:
- Installed apps
- Temporary files
- System & reserved
- Documents
- Pictures
- Other
If you see Installed Apps using 200GB+, it’s time to review your software list.
Uninstall apps you no longer use — especially games, editing tools, or old utilities.
🗂️ Step 4: Inspect the Windows Folder
Right-click C:\Windows → Properties
A normal Windows installation is between 25–45GB.
If you find a folder called Windows.old, delete it.
This is a leftover from an older Windows upgrade and may take up 20–30GB.
⚡ Step 5: Disable Hibernation (Frees up 15–32GB Instantly)
If you don’t use hibernate mode, disable it.
Open Command Prompt as Administrator, type:
powercfg -h off
Press Enter.
A large file called hiberfil.sys is deleted instantly, freeing up huge space.
🔧 Step 6: Adjust Virtual Memory (Paging File)
Right-click This PC → Properties → Advanced System Settings
Go to:
Performance → Settings → Advanced → Virtual Memory
- Uncheck Automatically manage paging file size
- Select drive C
- Choose Custom Size
- Set:
- Minimum: 4096 MB
- Maximum: 8192 MB
Apply and restart your PC.
This helps prevent unnecessary disk usage.
🧽 Step 7: Run Disk Cleanup (Admin Mode)
Search for:
Disk Cleanup → Run as Administrator
Select these items:
- Temporary files
- Thumbnails
- Windows error reports
- Recycle bin
- Delivery Optimization files
Delete them all.
🗃️ Step 8: The Most Important Step — AppData Cleanup
This is where most hidden storage issues happen.
Press:
Windows + R → type %appdata% → Enter
Click AppData at the top to access:
- Local
- LocalLow
- Roaming
These folders store:
- Hidden Adobe & video editing cache
- Browser data
- App scraps & leftover files
- Game cache
- Logging data
🟥 Critical Folder: Roaming
Right-click Roaming → Properties
Many users find:
- 50GB
- 120GB
- Even 200GB+ of hidden data
In your case, Roaming was 166GB, caused by Wondershare/Filmora storing raw recordings.
Delete:
- Old export caches
- Unused recording files
- Duplicate media folders
You instantly recover 50–150GB here alone.
Check Local as well
Example large folders:
- Adobe
- NVIDIA
- CapCut
- Temp video render folders
Delete only files you recognize.
🎉 Final Result: 150GB Recovered
Before: 32GB free
After full cleanup: 188GB free
That’s over 150GB recovered without installing a single tool.
🧩 Optional Q&A
Q1: Is it safe to delete Temp and %Temp% files?
Yes. They are automatically recreated and contain only temporary data.
Q2: Can deleting AppData break my apps?
Only delete folders from software you recognize. Never remove entire AppData folders blindly.
Q3: Is disabling hibernate safe?
Yes, unless you use the hibernate feature. Sleep mode still works normally.
Q4: Why is Roaming folder so large?
Apps like Filmora, Adobe, CapCut, and many game launchers store hidden caches here.
Q5: How often should I clean the C drive?
Once every 2–3 months is enough.
#Windows11 #WindowsTips #CDriveFull #PCMaintenance #DiskCleanup #TechGuide
