motorolla programming issues

hi im tying to get set up to program a motorolla cm300 deck radio and a motorolla ht1250 handheld radio i have maxton usb programming cables with drivers i have cps 5.12 for the cm300 and global tuner 2.15.00 for the ht1250 when i try and read the ht1250 hanheld i get a message that says read radio failed all softpot operational data is invalid please re read radio and the cps for the cm300 says error #512 unable to read check to see radio is connected radio is powered on and com port setting is correct ive tried all the usb port as well as 2 different computers one windows 8 machine and one windows xp anybdy have any ideas why ?