Why Photoshop Says a File Type Is Not Supported (and the Fix)

Step 1: find out what the file really is

The extension on the file name is just a label, and it is wrong more often than you would think. Chrome saves WebP images with a .jpg name when a site serves them that way, phones rename HEIC files when sharing, and people rename files by hand hoping it will help. Photoshop reads the first bytes of the file, sees a format that does not match the name, and gives up with the "not the right kind of document" message.

Drop the file into the image file type checker. It reads the same signature Photoshop reads and tells you the real format, the colour mode and whether the extension matches — nothing is uploaded.

The five causes, and the fix for each

WebP and AVIF: the version problem

Photoshop gained native WebP support in version 23.2, released in February 2022. Anything older needs the free WebPShop plug-in or a conversion first. AVIF support arrived later still, so a Photoshop that is a couple of years old will reject AVIF files outright.

If you cannot update — a work machine, a perpetual CS6 licence — convert the file. WebP to PNG keeps transparency; WebP to JPG gives a smaller file for photos.

HEIC from an iPhone on Windows

On a Mac, Photoshop opens HEIC through macOS. On Windows it relies on the system's HEIF and HEVC codecs, and without the HEVC Video Extensions from the Microsoft Store the file will not open. Converting the photos to JPG is free and avoids the codec entirely.

To stop the problem at source, set the iPhone to Settings > Camera > Formats > Most Compatible, which makes the camera shoot JPG.

Other messages that mean the same thing

• "Could not complete your request because it is not the right kind of document." — format and extension disagree, or the format is unreadable.
• "Could not complete your request because the file format module cannot parse the file." — usually a WebP or a damaged file.
• "Could not open because of a program error." — sometimes a corrupt file, sometimes preferences; try opening a copy of the file first.
• The file is greyed out in File > Open — Photoshop does not recognise the extension at all; choose "All Formats" or rename it correctly.

When conversion is the better answer

If the image is going into a design and then out to the web, converting it to PNG or JPG before opening is not a workaround — it is the normal workflow. Photoshop's editing happens in its own document format anyway, and a JPG or PNG source is what every other app in the chain expects.