Hard drive space disappearing and reappearing

[-ExcaL-]

sometimes my ssd space would go to 169gb free of 223 gb and then sometimes it would just jump back to 171gb free anyone know why this is happening

 

[nancyrobert2011]

Try this:
Press Start > Right click on Computer > Properties > System Protection (third dow on the top left) > Highlight C: > Configure. Now you should have this little window which tells you the story. With the 'Max Usage' slider you can change the size of your shadowstorage.