[Marcelo Machado Cardoso]

I have a cell phone where I can't write recovery or boot.img, it gives errors, even with the steps of SPD bootloader to unlock, done, he doesn't write the IMG ... you have some way to insert values for the PROP, which I believe must be blocking writing ???? without root access .... ????

[hovatek]

I have a cell phone where I can't write recovery or boot.img, it gives errors, even with the steps of SPD bootloader to unlock, done, he doesn't write the IMG ... you have some way to insert values for the PROP, which I believe must be blocking writing ???? without root access .... ????

I don't quite get what you're trying to achieve but there's little you can do without a signed image.
What is the device's model?