A customer can't upload a photo

Upload rules are set per option. Open the option set, select the upload option and check its settings.

• Allowed file types. The file must be one of the formats you allow. An Image upload option offers PNG, JPEG, JPG, WebP, GIF and SVG, and accepts any common image when the list is empty. A File upload option starts with PNG, JPEG, JPG and WebP and can accept a much longer list, including PDF. See Set upload rules: file types and photo size.
• Min image width and height. Under More settings. A photo smaller than this is refused on purpose, to prevent blurry prints. Lower it only if your product prints well at a smaller size.
• Max number of files. With Allow multiple uploads on, a customer can add up to the number you set (10 by default, 20 at most).
• File size. Each file can be up to 10 MB. Very large files also take longer on a slow connection, so ask the customer to try a smaller copy of the photo.

If none of these explain it, ask the customer which browser and device they used, then contact support with the product link.

Guide: Let customers upload photos and files