My games at the r4 are corrupting

I never used an r4 before,i have a clone of the r4 sdhc, and i try to use it at my dsi,i've put on it 20 games,some of them work,like warioware and super mario,but most of them dont,say that they are corrupted,and i dont know what to do, please help :D

Replying to #1

If it's so (your statement I highlighted in red), then get new rom copies.