Huge size difference between C drive and the its folders.

Hello,

My name is Alex and I bought a powerful laptop 2 years ago, but with a small C drive. I've later bought a second inside HDD, but now I struggle tu keep at least 10 GB free on C drive so the computer can run smoothly.

My problem is that when I right click on the C drive there is about 5GB free, but when I select all the folders from the inside of C drive, it says that there are only about 75GB used.

So please tell me what to do, or what's the issue with this huge difference.

Alex

Use WizTree free to see what it shows.
They have a Portable Zip available, no install needed.

Antibody Software - WizTree finds the files and folders using the most disk space on your hard drive

This happened to my external hd. I used smadav antivirus to run a scan on the hd and it eventually 'unhid' files and folder i didnt even know existed( this works if your hd is affected with virus). You also can try this, activate 'show hidden files' in ur pc settings (this should work if your hd is not virus-affected)

Thank you DavidE,
I used WizTree and this is my result. Please tell me how I can, or if it is safe to delete the large files from the system volume information. Because I have to do something to let the C drive breathe. I installed all the big programs that I use on D drive but it is still not enough.

Thank you dayzzy,
I scaned the C drive and there really was one infected file, which I deleted.

It might be your Restore Points.
You might need to delete some Restore Points and lower the max used space for System Restore.

What Anti-Virus do you use ?

Here a couple of tutorials that should help:
System Protection Restore Points - Delete
System Protection - Change Disk Space Usage

Thank you DavidE,
you were extremely helpful! Now my C drive has space to breathe. The slider was set to 20% and I moved it to 10% so I saved more than 10 GB. Not bad!

Yeah, sure. I use Avast Antivirus.