"I have a WD My Passport external which is not recognized on Mac, but I have stored many files on this external HDD. So can anybody tell me how to recover data from an unreadable external hard drive for Mac?"
WD My Passport external hard drive is able to work on Mac and Windows PC for data transferring or backup. If a WD My Passport external hard drive is not recognized by Mac OS, you had better make it clear if the problem is caused by external HDD error or Mac OS crash. You can connect the WD My Passport to another computer to see if it can work normally. Once you are sure that the WD My Passport is corrupted and becomes inaccessible, you had better stop performing any further operation to this external and then you can use data recovery software to get back lost data.
For an unreadable external hard drive data recovery, you need to rely on a professional data recovery program. iCare Data Recovery is a good solution for data recovery from any storage media including WD My Passport when it is not detected by Mac OS or other PC. You just need to plug the external to a PC, and this data recovery software will deep scan the external even if it cannot work normally. iCare Data Recovery is a read-only program which is compatible with Windows OS, so you should plug your external to a Windows PC in order to retrieve all lost data when the WD My Passport is not recognized on Mac. Now, you can follow the steps below to recover unreadable data:
Step1. Download and install iCare Data Recovery on Windows PC. Run the software and choose a proper scan mode.
Step2. Select the WD My Passport external and then wait the software to scan it.
Step3. When scanning is completed, you can preview found files and then save the lost data to another drive.
Everybody knows that the most important thing is to restore all lost data when a WD My Passport drive is not recognized on Mac, but many people still like to know the reasons why an external hard drive stops working on Mac. Here are some possible reasons:
An external hard drive might not show up on a computer when it is formatted improperly. As you know, when you buy a new external hard drive, it usually has FAT32 or NTFS file system. Both of file systems are able to be recognized by Windows OS, but it might become unreadable when you plug an external hard drive that has FAT32 or NTFS file system to a Mac computer. Therefore, if a WD my passport external hard drive is not recognized by Mac OS, but it is able to be compatible with Windows OS, you only need to format it to HFS+ file system which is able to be recognized by Mac OS.
As mentioned above, an external hard drive must be formatted properly so that it can be detected by Windows or Mac OS. However, sometimes, virus infection might corrupt the file system of WD my passport external hard drive and make it not show up when you connect the external to your computer. In this situation, you can recover all inaccessible data at first and then you can run antivirus software to scan the external hard drive and finally format the external into proper format.
Another situation is that the WD my passport portable hard drive can show up on Mac OS when you plug it to your computer, but the problem is that you are unable to access any data stored on this disk. In this situation, you can also check whether the external hard drive file system is compatible with Mac OS. If WD my passport external HDD has unknown file system, you can use iCare Data Recovery to recover files from inaccessible drive and then try to format the WD my passport external hard drive to HFS+ file system. If you want to use your external hard drive in Windows PC, you can connect it to a Windows PC and format it to FAT32 or NTFS file system.