I have no idea if this is the right area to post this but..

I have a problem with my quicktime;
I downloaded a program of 4 parts
I can watch part 1 perfectly,
but when I want to open the other ones
I get a fault it says: cant open because this video has a structure that quicktime cant open..

can anyone help me?

the files where .avi.001 files.. .avi.002 untill .004
I changed all from .001 to only .avi..