I've had this problem before. If I understand you, it could be any of the following....
1. Your computer might not work with the driver. This happened on our HP, but it will work on every other computer in our house. Try a different computer, even if its at school, work, library, etc.
2. Your ActionReplay memory card could just be, simply, corrupt. Which, in that case, you'd need to replace it.
I did both of these when it didn't work for me, and it worked after I did yet. Yet, I didn't change one variable at a time to determine the problem, so I really can't tell you for sure.