Re-Naming NDS Rom

I tried to put "Brain Training: Dr Kawashima's How Old Is Your Brain" onto my r4 card but it said the file name was too long. So i shorten the file name and now it wont work. Is there a special way to re-name nds filesThanks

Well you just rename it as usual from your computer I think.

This what i did, but got a message saying " renaming may make the file unstable, which it did.

Make sure you keep the extension as .nds
I don't think that mistake will happen though, well I can rename the files just fine.

You renamed it wrong. It only gives you that error if you change the file extension. And it doesn't make the file unstable, it just makes windows not know what to do with the file if you change the extension.Name it something like BT-HOIYB.nds

Thanks i hadnt left the ".nds". works fine now

Just to add if you rename the file to something less than eight characters, on some cards you will get a save file with .SAV at the end not .sav, this will give you a problem with the game recognising the save file next time you play it.