Windows C: drive missing space

[TheNopeman]

I'm currently in the process of moving windows to my new SSD, I have backed up everything onto a second HDD and I have trimmed, uninstalled and deleted unnecessary programs from my original HDD, by my count I have around 80GB ready to transfer, looking in my disk management I see an extra 15GB on a system partition however my Windows C: drive says that I have 167GB of used space? Any thoughts or ideas where this might be coming from?

(By my count I am looking at the properties of the different folders within Windows C😉

 

[MarkW]

Hidden Windows recovery partition.

 

[TheNopeman]

Ah I found 70GB of system restore point(s), thanks for the help!

 

[USAFRet]

Many things:
System Restore points
hibernation file
As above, a Recovery partition

Can you post a screencap of your Disk Management window?