Do you know if your friend reformatted the drive? With it connected to your Windows 7 look in Disk Magagement and see what it says about the drive. Look down by the bars it should give the format type for Windows it should be NTFS. I don’t know much about TestDisk a lot of people have used it to repair partition and have had good luck. There are some tutorials there. The Mac files is a puzzle so its best to do nothing and see if we can figure out what happened. It may have changed files in the partition data. This tool http://www.easeus.com/partition-recovery/ may be easier than the TestDisk. Read the tutorials for both.
Don’t do anything right now I’ll get back with you tomorrow. It’s late here now. I don’t know anything about Macs I’ll see if I can find somebody else to help. It’s better to wait than make it worse or unrecoverable just to hurry.
As far as I am reading your case I see that it may be a currently no recognition issue after plugging the drive to a foreign operating system before a formatting action, a u know this drive comes formatted to NTFS(NEW TECHNOLOGY FILE SYSTEM,) which it means that the drive is a Windows based drive, even doe is compatible with Mac it has to be formatted to FAT32 to be recognized in your friends Mac, it will be as a Read only status but not executable, WD only builds NTFS or HFS (HIERARCHY FILE SYSTEM) Apple based Drives, u can troubleshoot by doing this:
1 Check that your power cord is connected to the wall , this drive needs at leads 12v ,1.5amps & 18 watts of power running thru his powerboard, sometimes this is most of the cases that may take the drive to a non recognition in a computer. Take it out of the Powerstrip and take directly to the wall. This may resolve the issue.
Check in device manager >disk drives for drive recognition, also in disk management and it should have a blue bar and say healthy primary partition NTFS, 931.00 if no data stored, which is not your case because you have data in the drive . If all this options are showing in your computer the drive is OK,.
Security settings in the drive, if u haven’t dropped the drive or it has not suffered any falls that may take the drive to a non recognition, u may probably have a security settings in your drive, securing your drive makes the drive invisible in any operating systems , if no security settings in the drive go to step 4
Change the USB cable, as u know Mac sox computers does not supports USB. 3.0 connections for long time , this may take the drive to a jumping/eject status if a usb.3.0 is detected after a while, so maybe your USB connector is bad even doe your drive IS LOOKING FINE, so u may have to test with a different USB connector better if tested in a Windows computer.
Check another computer, take the drive to another computer, better if windows, to test the drive for recognition.DO NOT OPEN YOUR DRIVE BECAUSE THIS VOIDS THE WARRANTY ON IT without and approved authorization for wd , so you may call to get this authorization in case of data recovery.
If still no go , check online in the wdc.com website > support > data recovery > THE AMERICAS. In this section you will have a list of certified partners data recovery companies by western Digital, that can provide u with ISO certified service can get discounts on this companies just by being a WD customer , do not hesitate in calling for support of WD TECH AGENT, u have 30 days of free tech support and your warranty time left if needed for replacements.
So try this tips, IM pretty sure that it may bring the drive back . If not call for assistance they will do their best to help u with your drive. Phone number in the website in phone support in the support section in the right bottom side .
