Scratch disks are full ! How to change settings

[#1]

Hello! 

I got an error that my scratch disks are full when I try to open a file in Photoshop. I searched and it said I could change the free space from 6 GB to 1.5GB here at this link

https://helpx.adobe.com/photoshop/using/scratch-disks-preferences.html#Troubleshootscratchdisksarefu...

But when I open Preferences, I cannot select or deselect the active check box to a smaller amount.

Any suggestions? Thank you!

[#2]

Hello! 

I got an error that my scratch disks are full when I try to open a file in Photoshop. I searched and it said I could change the free space from 6 GB to 1.5GB here at this link

https://helpx.adobe.com/photoshop/using/scratch-disks-preferences.html#Troubleshootscratchdisksarefu...

But when I open Preferences, I cannot select or deselect the active check box to a smaller amount.

Any suggestions? Thank you!

[#3]

Hi

If you only have 6GB of free space for the scratch disk you're going to run into issues on an operating system level never mind Photoshop, you need to free up space on your system drive, you really need at least 100GB of free space for the scratch disk.

Do you have other drives available, what do you see when you open up the scratch disk preferences