ok are you naming it correctly? it needs to be exactly PC36IMG. the bootloader is programmed to look for this file name. if it is not named right, it will not find it. also it is programmed to look for the file on the root of the sd card which means not in any folder, just on the card. so i'm not sure what is going with why the bootloader is not finding the file. one of those two things is not being done right.
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