LGUP checks the current phone to see what specific model it is. In my case it's an LG v20 F800L. I'd like to install the H990 kdz on it instead because I don't want a bunch of Korean language apps that I can't read and I can't uninstall. When I try to load a kdz file using LGUP I get an error that says roughly

invalid kdz F800L->H990

Can LGUP be tricked about what model the phone is or the kdz file is? Otherwise, what other ways are there to install a stock kdz when it doesn't necessarily match the phone's specific model?

What I tried so far:

I ran grep on the kdz

grep -an "F800L" H990N20d_00_OPEN_HK_DS_OP_0920.kdz | less  #-a for binary n to show the line number. Piped to LESS because otherwise the output might do some funky stuff to your computer.

The search for the string "H990" showed 3 instances. Next I ran

sed -i 's+H990+F800L+g' 

to change instances of H990 to F800L. The new file size was 3 bytes larger, which was expected because F800L is one character longer and there were three instances. When I tried loading the new file to the phone using LGUP it just gives an error Error: KDZ file is invalid. so there's some kind of checksum.

recommended tags: KDZ LGUP

  • 1
    Firmware images are usually cryptographically signed (I assume this is also true for LGs KDZ files). Therefore even a changed single bit will make the file invalid. – Robert Oct 20 '19 at 13:58
  • If I can't change the KDZ, any chance I can change the phone? – Altimus Prime Oct 20 '19 at 14:09
  • 1
    You can try to root the phone and make any modifications you want. Anyway the two variants F800L and H990 seem to incorporate different LTE hardware (according to phonemore.com/specs/lg/v20/h990t they support diferent LTE bands), therefore your approach using a different firmware will never work. – Robert Oct 20 '19 at 14:14
  • Thank you for saving me from wasting anymore time in that direction. – Altimus Prime Oct 20 '19 at 14:35

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