A RESOLUTION error is given by Rapid Inspector when it finds an image with a resolution lower than the required resolution for print production.
To achieve good print quality, an image must be scanned (or generated) at the exact dimensions in which it will print. To correct a low resolution scanned image, usually the original hard copy must be rescanned at the appropriate resolution. If the image is generated from a digital file or vector file, it may be possible to regenerate it at a higher resolution. Check the resolution settings for the specific application in use.