Motorola i870 / i875

Hello all. For some reason, I can't transfer music or videos from my computer onto my phone. I downloaded what I had to download when I bought my phone and when I put the memory card into the computer, it looks as if it is transfering the music onto the memory card but when i put the memory card back into the phone, there is no music on it. I also have no idea how to transfer videos from my computer onto my phone! Can someone please e-mail me at [email protected] because I am totally lost and I hate this phone right now!