This error is indicative of an incorrect tile set number being entered in Net Profiler. Please ensure there are no typos when entering a tile set number (e.g typing an 1 instead of typing a capitol i). Additionally, the tile set being used is not the correct type of tile set to be used with this instrument. Verify the tile set number from the tile set (there is a certification sticker on the tile set with the certification date on it). The sticker also states the geometry (e.g. Sphere or 0/45) the tile set has been assigned to. Your instruments geometry and tile set should match. In the event that your tile set and instrument geometry do not match, please contact X-Rite Technical Support.