What if you linked external hard drive and can not access it?

usb - Detect and mount devices - Ask Ubuntu:


How to check disks tree structure and locate target disk:
lsblk


How do I find out my motherboard model?

lspci

How to mount

Manually Mount a USB Drive

A USB storage device plugged into the system usually mounts automatically, but if for some reasons it doesn't automount, it's possible to manually mount it with these steps.

1. Press Ctrl+Alt+T to run Terminal.
2. Enter sudo mkdir /media/usb to create a mount point called usb.
3. Enter sudo fdisk -l to look for the USB drive already plugged in, let's say the drive you want to mount is /dev/sdb1.
4. To mount a USB drive formatted with FAT16 or FAT32 system, enter:

   sudo mount -t vfat /dev/sdb1 /media/usb -o uid=1000,gid=100,utf8,dmask=027,fmask=137
   

   OR, To mount a USB drive formatted with NTFS system, enter:

   sudo mount -t ntfs-3g /dev/sdb1 /media/usb

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