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In order to wipe external storage of my android, I put the SD card in laptop and ran DBAN. It has become blank but not readable by mobile or laptop. Mobile says"SD card blank or has unsupported file system". formatting it does not help. Laptop does not open the card at all. Anyhelp to make it usable again?

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Does your computer OS report capacity/partitions/filesystem/anything correctly? Note that SD cards does not need partition tables or any other kind of MBR to work, however some devices (don't know about android) require that SD card has MBR in order to successfully recognize partitions and filesystems. – Sampo Sarrala Sep 26 '12 at 6:38
Laptop OS reports capacity wrongly,for eg, for all partitions, UBUNTU says "320gb Hard drive:Work" . where "work" is name of partition. – John Watson Sep 26 '12 at 6:56
up vote 1 down vote accepted

It's not readable because DBAN doesn't format the card. It wipes the card using a mathematically random sequence of writes. Format the SD card.

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as i said formatting did not help. – John Watson Sep 26 '12 at 6:16
do SD Cards contain some codes in it, which has been erased ? – John Watson Sep 26 '12 at 6:17
No. They don't have any special codes. I don't recall seeing your comment about formatting before. Are you sure you successfully formatted the card? The slide/switch for the SD card is set to read/write or unprotect(ed)? – John Sep 26 '12 at 6:34
android formats it without any error – John Watson Sep 26 '12 at 6:52
Try formatting in FAT32. – John Sep 26 '12 at 6:56

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