If the external hard drive is not recognized, you should look into the USB connection, the power supply, the cable, and try connecting it to another computer. It may also help to check Disk Management to see if Windows recognizes the physical drive. If Windows sees the drive but does not let you access it, do not initialize or format the drive if it contains important information. There is a possibility of using recovery programs that will be able to access the data from the drive. Notchox may be used to recover data from supported external hard drives.
