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I am using a Sandisk 8 GB micro SDHC card on my MileStone. The card is detected and mounted. I can read data from the SD card, but cannot write to it. There is no error when I attempt to write to the card.

It appears as if it's working fine, but after unmount and re-mount, the data written is gone. Even if I format it, it will restore to the previous state.

At last, I tried to format it, but the operation system formatting utilities were not working, it says

Windows was unable to complete the format

Then I use the "SD Formatter 3.0 Beta" from "", and it says

The nemory card is write-protected. Please release the write protect switch."

but I can't find any switch on my micro SDHC card or SD card reader.

I see some useful information on that web site. It says

The SD/SDHC/SDXC cards have a "protected area" on the card for the SD security function. The SD formatter does not format the "protected area". Please use the appropriate application software or SD host device which provides SD security function to format the "protected area" in the card."

I think my card may be wholly protected. How can I format it?

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migrated from Sep 3 '10 at 12:57

This question came from our site for professional and enthusiast programmers.

This should be on – Robusto Sep 3 '10 at 12:37
Your not alone, with the write switch been activated -… – JonWillis Sep 3 '10 at 12:48

Are you using a Micro SDHC adapter. Basically are you putting the Micro SDHC into a SDHC card, which in turn goes into the card reader.

I ask this because the adapter can have a write protect switch on it, even if the Micro SDHC doesn't. Example of write protect -

If not your card has gone faulty. Save your data and return it to scandisk for a new one -

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