Our system will reject jacket files for one of three reasons: 1. The file is too small to print clearly. All photos should be at least 1,200 pixels tall / wide (and our system will reject anything less than 1,000 pixels)2. The file size is too large. Keep it under 10mb!3. The file is the wrong type. Our system can accept PNG and JPG/JPEG photo files. Other formats like pdf or .ai files are not accepted.If you have any questions about your files, please feel free to contact us at contact@freestyle-vinyl.com!