My external hard drive was plugged in to my Macbook Pro (17" Mid-2010) and I lifted the computer a little and the external dropped off the table (it stayed connected and didn't hit the ground or anything.) However, I then had the error message saying the disk had not been ejected properly. Now the disk won't mount or show up in the Disk Utility or in the System Information. I have tried the other USB ports. I have tried resetting the PRAM. The disk will not mount on our family Mac desktop either. The light on the external hard drive goes on as normal when it is plugged in (no individual power source,) as well as makes the standard noises. If this is a communication error with the external the laptop, how do I reset the permissions? If this is a hard drive error, it would surely be a controller error and not a disk error (It was inactive at the time.) How can I salvage my data?