This error typically indicates that the encoder strip is not being detected by the sensor on the back of the printer carriage. The encoder strip is the clear strip that spans the left to right distance where the printer carriage (cartridge holder) and arm intersect. The strip has tiny black lines that are read by a sensor on the back of the carriage. This tells the unit where along the horizontal (left to right) path the arm/and or cartridges are located. If you receive this error when you start up the unit it probably means that the sensor can not read the encoder strip. Check the following:
1. Make sure the strip is not missing. It may have broken or the spring (far left side) that provides tension may have fallen off.
2. Ensure it is not twisted as it goes behind the carriage. It could be displaced from the notch behind the carriage. You may be able to put the encoder strip back in place. It slips in a hidden notch on the back of the carriage from the bottom. Unfortunately, you are not able to see the notch so you need to put it back in place blindly.
3. Inspect the encoder strip for ink, dirt, or grease that may be blocking the sensor from reading it. If necessary lightly clean the strip with a mild cleaner. Do not scrub, since you may clean of the lines that are printed on the strip.
If you are unable to solve the issue, the unit may need repair. Please contact technical support.