When you open an image in Photoshop, one of the following errors occurs:
- Could not complete your request because it is not a valid Photoshop document.
- Could not complete your request because an unknown or invalid JPEG marker type is found.
- Could not complete your request because the file-format module cannot parse the file.
- This is not a valid Portable Document File (PDF) document. It cannot be opened.
It's important that the extension you add to the filename is the appropriate one for the actual file type of the image. When you choose a format from the Format pop-up menu in the Save As dialog box, the appropriate extension is added automatically. If you entered the extension manually, you could have typed in an extension that doesn't match the file format of your file.
Filename extensions are hidden by default. To turn them on, perform the following steps:
- In Finder, choose Finder > Finder Preferences > Advanced.
- Select Show all filename extensions.
Turn on filename extensions as in Solution 1, and view your images in Finder or Windows Explorer. Then, check to see of there are two extensions on your files. If your images have two extensions, such as:
Remove the last extension so the file is named:
Open the problematic image in a photo app such as Preview (on macOS) or Photos (on Windows). Now save the file again as a JPEG image from within such an app. Try opening the file again in Photoshop.
Validate your hardware to make sure that there are no hardware failures, such as with an external hard disk or network.