Photoshop needs to use disk space to store temporary files, the disk(s) used for this is called the scratch disk.
If you only have one hard drive then that is the scratch disk and the error you are getting means that disk is full so PS cannot write any temporary files.
The only solution is to clean up your hard drive, or install a new one and use it as your scratch disk (you can set this in preferences).
Give your photos a professional finish with sharpening in Photoshop. Learn to enhance details, create contrast, and prepare your images for print, web, and social media.
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