About 2 months ago when everyone was having this issue, a Verizon tech posted this:
Noah from Verizon Wireless on Connecting to a PC:
If you intend to transfer files between your SCH-I500 (Fascinate) handset and your computer, then you won’t need to install a driver. All you would need to do is to set the phone to mass storage and have a memory card inserted in the device for it to be recognized by your computer.
Ensure that the Memory Card is properly inserted into the device > Ensure that the USB mode is set on Mass Storage on the phone: Select Menu, Settings, Select USB settings, Select Mass storage even if already selected, Press Home key to return to the home screen.
NOTE: FOR Windows Vista/XP/7 OPERATING SYSTEM >Make sure that USB debugging is unchecked: Select Menu, Applications, Development, Uncheck all three options (USB debugging, Allow mock location, Stay Awake).
NOTE: FOR MAC COMPUTER >Make sure that USB debugging is checked: Select Menu, Applications, Select Settings, Development , Check USB debugging and uncheck other options (Allow mock location and Stay Awake)
*Connect the USB data cable to the device and a laptop or PC * After the USB icon appears in the Notification Drawer, pull it down * Select USB Connected * Select Mount > On the PC, navigate to the Removable Disk assigned to the device.
This can be done through the automatic pop up screen or My Computer. Drag and drop (copy and paste) files from other locations of your PC to this folder.
Make sure that the USB cable is a Samsung genuine accessory.
Here is the step by step method that I use for my PC:
Transferring the Fascinate's files to a PC: