pocketbook 840 read only problem questions

[markA]

I have read many topics about sd micro card not working, cloning, etc.
But i have some questions. I have a pocketbook 840 that works, but does not remember the page of the book. So this must a problem of the internal SD card.
I tried to repair the SD with some linux commands i found. that did not work.
I wonder if i use dd or any other tool to get an image, is this image any good?
Is the problem solely the SD card? Or is the image not good?
What i mean : if i go through the whole process, is the image i use any good?
Or do i need some new image?

And if the image is ok to use, could i format the sd card, and then rewrite the image? what exactly is the read problem? is this a hardware failure?

Then i also wonder if i clone the sd, why must i change the size with hex editor? will the clone not make a 16 GB card 4 GB again?

hope some expert can help me. anyway, thanks for reading!
Mark

[emmgrr]

I got the identical Problem last week,
internal system microSD had turned readOnly.
...
Reading the various hacky solutions here was rather bewildering.
So i wrote to service@pocketbook-int.ru and asked for a new firmwareImage for a new microSD-Card.
...
They need the DeviceSerialNumber, the SDSN of the new microSD and a picture of the sticker found inside the device on the PCB.
...
After sending these three Informations and 5€ via Paypal, i could download the new customized fwImage.
...
Next i used androidApp etchDroid to write the image to the formatted new microSD.
Inserted the Card in the cardHolder on the PCB and switched on.
Next the Device started to flash and partition itself during ca. 3m.
...
Now everything works as before, plus an extra internal MemoryBoost due to the 32gb SystemCard.
...
Conclusion :
Better not bother with the tricky Linux Hacks,
and instead get a new customFW from PocketbookRU directly

[emmgrr]

The old HowtoOpen Tutorial :
https://wxcafe.net/posts/pocketbook_...mbly_and_root/

[markA]

thanks for responding. i decided to do the same as i got no response.
it worked out great. and it has the advantage that it can be updated.
but still questions remain : what exactly causes this problem? is the card really bad? or is it just a case of rebuilding the partitions.
anyway, it is good that there is support. i also would advise not to bother but to contact pocketbook directly.

[emmgrr]

Apparently this readOnly issue happens sooner or later, simply depending on usage.
As on these older models, upon booting, the fileSytem is not being checked for errors.
So my simple solution is to get a really good microSD, with the Cards builtIn errorCorrection eventually doing a better job than the original noNameCard.