Hello,
I’m sorry if I posted this in the wrong section, correct me if I’m wrong.
I have been a member of this forum for a month or so now, looking around for some sort of solution or guide on what to do to solve a problem I have been having recently with my ME7.1 4Z7907551C tip 2.7. I want to write my modified L box file(lambda after cat off, checksums calculated by me7sum.exe) onto it
I’m having issues with writing  to this particular ecu. Ktag tells me that it’s hardware is not supported(even though it reads and writes 4Z7907551D perfectly fine, the only difference I have found is that on the D box there is a 29f800bb flash and on the C a 29f800bt). So I tried with a MPPS v18, first by putting it into boot mode by grounding pin24>power>ignition>taking ground off after 5s. It IDs the ecu fine reads ok and everything but when I try to write it immediately tells me that there is some sort of programming error.
So I boot it by grounding pin24>power on>take ground off after 3s, using this method I can write but it stops around the 97% mark with a “Programming error”. Tried both using “fast write” and “force full write” both unsuccessful. Neither the ori nor the modified can be written. After reading the written file I compared the file I wanted to write and the one that was physically on it using Winols, and it looks like a bunch of addresses at the beginning are missing. The car of course dosent start. All of this is done on the bench, with power supply set to 13.8V. I hope I gave all the necessary info.
Could this be a caused by a locked ecu?
I would be really grateful for any help or suggestions on what to do/try.
Thanks, Kacper

Could this be causing by issues?

Problem solved.
Soldered in the correct 29f800bb flash.
Thanks for the help!