After you plug the phone into the pc, check the status bar of your phone. There should be a USB Connected link there to select which will give you the option to Mount the phone. Once you've done that your pc should see your phone ok. Don't forget to remove your phone from the pc using the tray icon before selecting Unmount from the phone. I hope it would help you. :)

The instructions are on pages 94 and 95 of the full manual.

Ericwatson's instructions are slightly incorrect. According to the manual you can connect as a mass storage device but this only accesses the memory card. After you connect the usb cable you have to Open the notifications panel and select USB connected → Connect storage to PC → OK.

Here is a complete user experience review on Samsung Galaxy Y Pro Duos dual SIM phone. I’m using this phone for more than two months and recently the major bug was fixed on this model with the software update. Therefore, this is the correct time to share my experience and recommendation on this model. Samsung Galaxy Y Pro Duos – Model BT5521 is an entry level Android powered Dual SIM phone from Samsung. The price is very reasonable and features are good for the price. You are not going to miss anything important, at the same time not going to get anything extra from this phone for the price.