How to Fix Photoshop Scratch Disk Full Errors

Troubleshooting steps and fast fixes to free up space for photo editing

Sometimes when you try to perform an action in Adobe Photoshop, you might get an error message that reads, "Could not complete your request because the scratch disk is full."

To prevent the Photoshop scratch disk is full error, you need to change how Photoshop uses your computer's memory.

Information in this article applies to Adobe Photoshop CC for Windows and macOS.

The Photoshop Scratch Disk preference is shown

What Causes the Photoshop Scratch Disk Is Full Error?

The Photoshop scratch disk refers to your hard drive. Photoshop uses the hard drive as temporary swap space, or virtual memory, when your system doesn't have enough RAM to perform an operation. If you only have one hard drive or partition in your computer, the scratch disk is the drive where the operating system is installed (for example, the C: drive on a Windows system).

When that drive runs out of space, it prevents Photoshop from working properly. For example, if Photoshop crashes in the middle of an editing session, this improper shutdown may leave large temporary files on the scratch disk. Consequently, Photoshop may not be able to reopen, so you must perform some troubleshooting on the hard drive.

For more on how Photoshop CC uses RAM and scratch disk space, search for assigning scratch disks in the online help for your version of Photoshop.

How to Fix the Photoshop Scratch Disk Full Error

Follow these steps in the order presented to troubleshoot the scratch disk is full error in Photoshop:

  1. Free up disk space. Clear some space on the Mac or Windows drive that is defined as the scratch disk in Photoshop Preferences. For best results, use a free disk space analyzer tool like Disk Cleanup.

  2. Delete Photoshop temporary files. You can safely delete temporary files associated with Photoshop to free up scratch disk space. Photoshop temp files are typically named ~PST####.tmp on Windows and Temp#### on Mac (where #### is a series of numbers).

  3. Defragment the hard disk. It's possible to get the scratch disk is full error when the scratch disk drive has free space. This is because Photoshop requires contiguous, unfragmented free space on the scratch disk drive. If you get the error message when the scratch disk drive shows a good amount of free space, run a disk defragmentation utility.

  4. Clear the Photoshop cache. If you can open Photoshop, delete temporary files from within the program by going to Edit > Purge > All (on Windows) or Photoshop CC > Purge > All (on Mac).

    Purging the cache prevents you from undoing recent changes you made to images.

  5. Clear Crop tool values. If you get the error when cropping an image in Photoshop, it could be because the values in the options bar for the Crop tool are in the wrong units. For example, entering dimensions of 1200x1600 when the units are set to inches instead of pixels creates a large file that could trigger the scratch disk is full message. To prevent this problem, select Clear in the options bar after you select the Crop tool.

  6. Change the Photoshop performance settings. Go to Edit > Preferences > Performance (on Windows) or Photoshop CC > Preferences > Performance (on Mac), then adjust the sliders under Memory Usage to increase the amount of RAM that Photoshop is allowed to utilize.

    Setting the memory usage above 80% can cause the computer to run slow.

  7. Change or add additional scratch disks. If possible, create a new hard drive partition for the Photoshop scratch disk. Although Photoshop functions with a single scratch disk on the system partition, you can improve performance by setting the scratch disk to be the fastest drive in your system.

To change the scratch disk location and establish additional scratch disks from Photoshop Preferences:

  • On Windows, select Edit > Preferences > Scratch Disks, or press Ctrl+Alt.
  • On macOS, select Photoshop CC > Preferences > Scratch Disks, or press Command+Option.

If your computer has a fast solid-state disk drive (SSD), use the SSD as the scratch disk. Don't use the same hard disk drive (HDD) where the operating system is installed or where the files you edit are stored. Also, don't use a network or removable drive.