Due to software updates done at the dealership sometimes, there is a discrepancy between the number in the ECU and the numbers in the Mini Maxx tuner.  This issue is responsible for nearly 100% of the tech support inquiries we get for this tuner.If your tuner shows "Unrecognized Part number" when you install your tuner:Write down the file that is missing. Remove the SD card from the side of the tuner and put it into the provided adapterPlug the SD card adapter into a USB port of your computer, open the SD card drive in your windows explorer and find the correct folder that your truck is listed under (see below for which folder is for your model year below)Find a file that is close to the one displayed in the error message, right-click the file that closest matches, and click on "copy".  Then right-click an empty spot in the folder and click on "paste"You now have a file that is named XXXXXX-Copy.MM.  Right-click this file and click on "rename".  Rename that file to exactly what the error message listed as the unrecognized part numberTake the SD card out of the USB adapter, insert it back into the mini maxx and try to flash the truck again.So for instance, if you were missing file FC20BLK.MM try looking for FC20BL.MM or FC20BJ.MM, copy that file, paste it, and rename it FC20BLK.MM*If the file it's asking for starts with "SPRA" (ie SPRA020.MM) that indicates that the PCM is currently locked from a previous Spartan branded tuner.  You will not be able to modify the PCM until you remove the Spartan tune file.  If you are unable to unlock the PCM with the original Spartan tuner, you will need to have a dealership flash your truck back to stock before you can load any other tunes on it.* To find the right folder see the information below:For 2011-2012 model Fords: "FORD67"For 2013-2014 model Fords: "FORD13"For 2015-2016 model Fords: "FORD15" The fix listed above has had a 99% success rate, the handful of times this didn't work the solution was to follow these steps but then select a different year of truck.  For example, if you have a 2015 model year and after creating the correct file in the FORD15 folder it still gives you the unrecognized part number error, press the Menu button, Change Vehicle and select a 2016 Ford instead of selecting the 2015 Ford.Between these two fixes we have a 100% success rate fixing the unrecognized part number error.