Hi guys. I cant read or write to 14 sector on my nfc tag. What to do? Here is TagInfo screenshot:
I lost access to it from the moment the tag was attached to the keys. I wanted to format it and write my address, but formatting didn’t work.
I lost access to it from the moment the tag was attached to the keys. I wanted to format it and write my address, but formatting didn’t work.
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Is it a magic tag or a normal Mifare Classic 1k?
A single sector failing after attaching it to a keychain sounds very weird, you’re sure you haven’t written something to it before and messed up the access conditions? (That’s the bytes between key A and key B, and you can configure that to disable reading or writing to different parts of the block.)
On the other hand as far as I know there is no way to disable reading access conditions when using key A, and your dump seems to show that key being used, so this seems unlikely.
Have you tried another app or reader?
Edit: doing some more research some people seem to mention the card locking itself if you write all zeroes. c# - MIFARE Classic - What could cause "All-zero key" and "Unknown key" error? - Stack Overflow
Which seems to contradict the datasheet on page 12, so not sure anymore…
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Here is full log from TagInfo: https://pastebin.com/raw/cHb3MDYn
I really just attached it to keychain, and 14 sector gone bad. Here is screenshot from MCT:
Nfc tools says, that there were problems when reading tag.