External hard disks are a very popular portable device which are capable of transferring large amounts of data from one device to another. For keeping backups of the internal hard disk of a computer, a external hard disk is a very useful tool. But sometimes people face different kind of problems with external hard disks. One of the most common problems is undetected hard disk or unrecognizable device. There are some easy ways to recover data from that particular external hard disk which is undetected.