Invisible 18 GB on C hardisk

[Mmat]

Hello,

 

When I was freeing up some space on hard disk, I noticed that I have over 18 GB difference between size of files of hard disk and current size of hard disk. I have cleaned my pc with CCleaner and made sure there is nothing in Recycle bin. But there are still those 18 GB that I don´t know what are used for (yes I have all invisible files shown). 

 

I´m running W8.1  64bit for about 1 year without reinstall.

 

Any ideas what could I do except reinstalling?

 

Thanks in advance,

 

Mmat

[Grrizz]

Check: System -> advanced system settings -> system protection -> Configure (with C: selected)

[paradigm249]

hi

try disk cleanup

[Matt420740]

Its normal, re-installing will do nothing. 

 

Windows allocates space for metadata.  Right click any of those files, then click properties, and you'll notice 2 sizes, "size" , and "size on disk"

 

Notice the "size on disk" is always larger, even if by small amounts, because of metadata that is not calculated when you look at the size of files.  But it is calculated when you look at the size of the disk.  Which is why the discrepancy. 

[Mmat]

Hadn´t thought of that but still only 4 GB.

[Matt420740]

Its normal, re-installing and disk cleanup will do nothing. 

 

Windows allocates space for metadata.  Right click any of those files, then click properties, and you'll notice 2 sizes, "size" , and "size on disk"

 

Notice the "size on disk" is always larger, even if by small amounts, because of metadata that is not calculated when you look at the size of files.  But it is calculated when you look at the size of the disk.  Which is why the discrepancy. 

Here is a screenshot of what I'm talking about

 

[TomvanWijnen]

Use a program like "file sniffer" to find out where the space has gone to.

[Mmat]

Matt420740 I see what you mean. TY. I didn´t know there was difference.

 

So there is nothing else I could do? 

 

I also found some topics about W10 pre downloading via Windows upgrades. 

Couldn´t this be that case?

[Matt420740]

Yes that can also contribute to the problem. 

[SteamSmagjus]

Surprisingly pagefile.sys and hiberfile.sys were not mentioned yet. Those could theoretically attribute to much more than 18GB.

 

Use TreeSize free started as admin too see those and all other files. Don't just delete them though as they are system files.