Which game are you trying to run through it? You might need to change the "Save Type" settings for the game to run.
Click on "Options", then click on "Emulation Setup".
Try changing the "NDS Cartridge Backup Media" option, and see if the game will run.
Click on "Options", then click on "Emulation Setup".
Try changing the "NDS Cartridge Backup Media" option, and see if the game will run.