You receive the following error when attempting to take a measurement:
Leica Error 256: “Receiver signal too high”
This occurs when there is too much light interfering while the laser is attempting to take a measurement. Usually this is due to a brightly lit window allowing too much light onto the surface the laser is pointed at. Imagine a camera taking an over exposed picture and the result is a predominately white picture. This is the same concept as to how the laser is viewing the area.
Try to block out some of the light before taking the measurement or position the laser in a location that doesn’t have the light shining directly at the laser.