Hi Jarvis,
Thank you for your reply. I've checked both of the thread but I couldn't figure out.
My experiment starts with a jpg file followed by a series of questionnaires. I've just tried Sample 3 "race" and pressed a key when the instruction (instruct. jpg) was shown. The same message "run time error 9 when press keys by accident" appeared and had to terminate MediaLab.
Is this anything to do with my computer?
By the way, I'm using V2006.
Thank you