Unable to install Mavis Beacon Typing program from pendrive.?

I copied Mavis Beacon Teaches Typing version 11 on my pendrive and tried to install it on my netbook which has no optical drive. While installing, progress bar got upto 100%. After that, i got an error message: "Could not execute the external program. G:\SETUP\401COMUPD.exe" Here G is my pendrive. I tried to install it on a desktop computer. I got the same error message. But when i installed the program on that desktop using the program CD, I could install it. I want to install the program on my netbook using pendrive. How do i solve this problem?