I would suggest you put the data from the SD card back on the computer (if you didn't just copy it), then insert the card into the phone and let it format it.
Once it has been formatted to work with the phone, you should be able to just connect the phone, via USB cord, to the computer and transfer the files that way. No need to pull the card back out of the phone.
Your computer should recognize the device and allow you to transfer to it. Now if the phone will able to read the files you have placed on the card, I can't say. It will depend on what kinds of files you are putting on it.