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nhedgehog · 01-29-2017, 03:07 AM

If you make an image of the SD you will find the serial number of the device at hex:5B00000
Changing that will result in constant bootloop.
My guess is, that serial number, SD-CID (and probably the SD size too) are somewhere encrypted together. Changing one of this resulting in constant bootloop.
Further guesses suggest, that the file monitor.app is checking the correct CID and serial number. Since it is the first app, that is called after start.
One could either have a closer look at this app or find the encrypted section where CID and serial number are stored and reverse this somehow. Neither approach seems to me worth the effort, since Pocketbook is helping when the internal memory gets corrupted.

Did you try fsck -r /dev/sd?? with your card?

You can check the state of the internal card by making a backup of it (I described the howto somewhere in this thread) and formating the card. If the card is usable on another device (computer/tablet) after formating, you are lucky and have only an error in the filesystem. That is solveable (see abaove). The image can be rewritten on the same SD without problems. I use USB Image Tool 1.72 from Alexander Beug for creating and rewriting the Image.

01-29-2017, 03:07 AM	#31
nhedgehog Guru Posts: 746 Karma: 619508 Join Date: Sep 2013 Device: EnergySistemEreaderPro, Nook STG, Pocketbook 622, Bookeen Cybooks ...	If you make an image of the SD you will find the serial number of the device at hex:5B00000 Changing that will result in constant bootloop. My guess is, that serial number, SD-CID (and probably the SD size too) are somewhere encrypted together. Changing one of this resulting in constant bootloop. Further guesses suggest, that the file monitor.app is checking the correct CID and serial number. Since it is the first app, that is called after start. One could either have a closer look at this app or find the encrypted section where CID and serial number are stored and reverse this somehow. Neither approach seems to me worth the effort, since Pocketbook is helping when the internal memory gets corrupted. Did you try fsck -r /dev/sd?? with your card? You can check the state of the internal card by making a backup of it (I described the howto somewhere in this thread) and formating the card. If the card is usable on another device (computer/tablet) after formating, you are lucky and have only an error in the filesystem. That is solveable (see abaove). The image can be rewritten on the same SD without problems. I use USB Image Tool 1.72 from Alexander Beug for creating and rewriting the Image. Last edited by nhedgehog; 01-29-2017 at 03:24 AM.