Cause analysis
First, it may be that your usb interface has insufficient power supply. We suggest you connect both interfaces.
Second, the drive letter is not allocated to your mobile hard disk. You can go to the control panel, manage tool options, computer management, and disk management options to assign the drive letter!
Third, after the partition table is lost, the system will prompt you to initialize it. Therefore, you can fix the partition table.
Solution
1) Download and install the DiskGenius software in the system,
2) open DiskGenius. On the main page, right-click the hard disk to be repaired on the left,
4) select "restore partition table" in the menu list ",
5) you can access the service after the software is repaired.
Or
If the mobile hard disk contains important file data, we recommend that you use a USB flash drive to enter the PE desktop. Then, in PE mode, copy important files from the mobile hard disk to your computer for backup, after formatting the hard disk with the Diskgen tool or re-partitioning the mobile hard disk, copy the backup file to move the hard disk. This generally solves the problem.
Of course, if you cannot solve the problem above and there are important data on the hard disk, we must not format the hard disk at will. At this time, we can ask the data recovery company to help restore the data, in general, this is easy to recover. You can recover about 300 pieces of data, because this is because the loss of the hard disk partition table is not the hard disk is broken, so it is very easy to use the recovery tool.