Hello, I have the C51 version 5 compiler. However we upgraded our computers and tried to install the program on a new computer with XP professional operating system. During the fisrt step in the compilation there is the message "no dongle found:. The dongle medic regodnizes the dongle as being a pro dongle. I have also downloaded the a new driver from the rainbow site. The dongle is still not regodnized. Please help me out. Best regards Gottfried