trouble with r4 revolution card(loading)

hello to everyone can anyone help i bought 4 r4 revolution cards and only one of them is working properly the others when i insert the card into the ds and switch it on it says its..... loading...... but never actually loads I've put the SD card into the other card that works so it has nothing to do with the SD card (well i think its nothing to do with the SD card) but if anyone has any opinions I'm open. has anyone else had this problem???? i bought the cards for my kids and they r doing my head in coz they cant use them?? can anyone tell me how to identify a fake r4 card to a real one???

Make sure they all have the correct firmware. There are quite a few cards that carry the R4 name, so you may have different ones.

Yeah, check your firmware. If you have a regular R4 card, you can find the latest firmware here:http://r4ds.cn/download/r4_v1.18_kernel.htmlIf you have an R4 II, I'm sure someone else on here can point you in the right direction. I think in this case, it would be best if you deleted everything on each of your SD cards and re-installed the latest firmware.

They all need their specific firmware, look at http://www.linfoxdomain.com/ds/, and if so, could easy be fakes.