Sd card – Disable write-protection on Micro SD

My task today is to open up and copy some files to 700 brand new micro SD cards.

As I get going on this task I am finding that some of the Micro SD cards are telling me “sorry this drive is write protected”

To copy the files I am using a standard SD to micro SD card adapter, and a USB SD card reader / writer.

I have ensured that the switch is set to OFF on all of my adapters. As soon as I get a Micro SD that tells me it is write protected I can use the same adapter with another micro SD and it works fine, so I know the problem is not with my adapters.

My question is: How can I disable the write protection on a Micro SD card? This eHow article seems to indicate that there is also a physical switch on Micro SD cards. However I have personally never seen a Micro SD with a physical switch, and none of the ones I am using today have said switch.

Since these cards are brand new and thus empty are the ones that are telling me they are write protected simply useless? Could this be caused by some sort of defect in the cards?

Solution:

Dust out your adapter.  The sensor inside of it may be dirty and not recognizing the position of the switch.

I would also try another SD<->MicroSD adapter.

If you still experience problems, try putting a questionable SD card inside of a phone.  I’d say if you get 2 or 3 cards that work fine in a phone, you should replace your USB card reader, see if maybe there is an issue with your USB connection, or use Linux to perform the task if possible which tends to behave a lot better regarding removal/insertion of USB devices, disks, and volumes than Windows (OSX also likely behaves a lot better).

If you find that the MicroSD cards are actually write protected (which should not be possible – the host/card reader is responsible for implementing the write protection and switch sensing, not the microcontroller in the card), I’d keep the bad ones and demand a refund.