How do you transfer music from pc (itunes and such) to the LG Venus?

I installed the cd first which then directed me online to the V CAST Music Manager, but when i install that it says that its installing the USB modem drivers. Then I went to Verizon Wireless and installed VZAccess Manager and V CAST Music with Rhapsody. Ive installed all these programs and plugged the phone into my computer, but when I try to sync the music or data, the phone says "connect fail" and to "please check your cable connection to the PC."