When opening a file, PhotoShop creates a scratch disk three to four times the size of the actual file. For example, if you try and open a 10MB file, the scratch disk it attempts create ranges from 30MB to 40MB. There may not be enough acutual room on the hard disk to open large files. If you have an external hard drive, with enough storage space, you can set the prefrences in PhotoShop to create the scratch disk using a different drive with more storge space. If the problem persists you need to talk to Adobe Technical Support.
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