how to unlock sd card?

I saw the reference to R4 cards and the Nintendo DS....
Which model R4 is it?
Some model R4 cards will not work in certain DS models, for instance:
The basic R4 card WILL work in a Nintendo DS but NOT in a Nintendo DSi.
Also, certain R4 cards will only recognise MicroSD cards upto 2GB in size, so if you have tried putting a 4GB card in and it isn't working, try going back to a 2GB size.
If you want to use a 4gb or larger MicroSD in an R4 make sure you have a R4i-SDHC model.
Another cause for R4's not to work is if you haven't copied the correct firmware files onto the microSD card thats inserted inside it, say if the MicroSD is blank.
If it is nothing to do with the above make sure none of the pins have snapped off inside the DS cartridge slot.
This was a common problem on early DS models leaving them to display "NO CARD INSERTED IN SLOT 1"
Looking into the slot you will see a row of gold pins, make sure none are missing.

Drew

DrewKrew
March 2011

yes i have does that and the slot says no card in slot 1 i have just but it in me daughters and it works

nicola
February 2011

the r4 will work in my daughters ds but not in my sons just says in my son not card in slot 1 when there is

nicola
February 2011

On the side of the SD card is a bit that slides up and down.slide it to the unlock position

Tech
February 2011