I would be happy to see if we can help with your file transfer. If it is the myTouch 3G, try these steps:
***Steps are very similar for all myTouch devices
To copy files from a computer to a memory card using a USB cable, follow these steps:
- Connect the device to your computer using the USB cable.
- From the Home screen, touch the top of the screen and drag down to display the notifications window.
- Touch USB connected.
- The Removable Disk window appears on your computer screen.
Click Open folder to view files using Windows Explorer and click OK.
- Copy and paste or drag and drop a file from your computer to a folder on your device.
- When you are done moving files, click the Safely Remove Hardware icon on the computer.
- Click Safely remove Mass Storage Device.
- Disconnect the device from the computer.
If you need further assistance, please let me know