External HDD partition not showing

I have problem with an external HDD. I am using Debian Jessie The partition is not showing, I can see only the device:

# ls /dev/sd*
/dev/sda  /dev/sda1  /dev/sda2  /dev/sda3  /dev/sda4  /dev/sda5  /dev/sda6  /dev/sda7  /dev/sda8  /dev/sdb

but:

# fdisk -l

Disk /dev/sda: 465,8 GiB, 500107862016 bytes, 976773168 sectors
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 4096 bytes
I/O size (minimum/optimal): 4096 bytes / 4096 bytes
Disklabel type: gpt
Disk identifier: DAE15A13-F263-4EF7-BE6E-0CFE86B52097

Device         Start       End   Sectors   Size Type
/dev/sda1       2048    821247    819200   400M Windows recovery environment
/dev/sda2     821248   1435647    614400   300M EFI System
/dev/sda3    1435648   1697791    262144   128M Microsoft reserved
/dev/sda4    1697792 473337855 471640064 224,9G Microsoft basic data
/dev/sda5  942671872 976773119  34101248  16,3G Windows recovery environment
/dev/sda6  937789440 942671871   4882432   2,3G Linux swap
/dev/sda7  906539008 937789439  31250432  14,9G EFI System
/dev/sda8  473337856 906539007 433201152 206,6G Linux filesystem

Partition table entries are not in disk order.

or:

# parted -l
Model: ATA ST500LT012-9WS14 (scsi)
Disk /dev/sda: 500GB
Sector size (logical/physical): 512B/4096B
Partition Table: gpt
Disk Flags: 

Number  Start   End    Size    File system     Name                          Flags
 1      1049kB  420MB  419MB   ntfs            Basic data partition          hidden, diag
 2      420MB   735MB  315MB   fat32           EFI system partition          boot, esp
 3      735MB   869MB  134MB                   Microsoft reserved partition  msftres
 4      869MB   242GB  241GB   ntfs            Basic data partition          msftdata
 8      242GB   464GB  222GB   ext4
 7      464GB   480GB  16,0GB  ext4                                          boot, esp
 6      480GB   483GB  2500MB  linux-swap(v1)
 5      483GB   500GB  17,5GB  ntfs            Basic data partition          hidden, diag

This is the syslog:
Jan 28 12:34:19 pcdigigi kernel: [ 2661.609618] usb 2-3: new high-speed USB device number 7 using xhci_hcd
Jan 28 12:34:21 pcdigigi kernel: [ 2663.199813] usb 2-3: New USB device found, idVendor=058f, idProduct=6391
Jan 28 12:34:21 pcdigigi kernel: [ 2663.199821] usb 2-3: New USB device strings: Mfr=1, Product=2, SerialNumber=0
Jan 28 12:34:21 pcdigigi kernel: [ 2663.199825] usb 2-3: Product: USB TO IDE Bridge
Jan 28 12:34:21 pcdigigi kernel: [ 2663.199828] usb 2-3: Manufacturer: Generic
Jan 28 12:34:23 pcdigigi kernel: [ 2665.298226] usb-storage 2-3:1.0: USB Mass Storage device detected
Jan 28 12:34:23 pcdigigi kernel: [ 2665.298623] scsi4 : usb-storage 2-3:1.0
Jan 28 12:34:23 pcdigigi mtp-probe: checking bus 2, device 7: "/sys/devices/pci0000:00/0000:00:14.0/usb2/2-3"
Jan 28 12:34:23 pcdigigi mtp-probe: bus: 2, device: 7 was not an MTP device
Jan 28 12:34:43 pcdigigi kernel: [ 2685.848591] scsi 4:0:0:0: Direct-Access     Generic  Void Disk        9.02 PQ: 0 ANSI: 2
Jan 28 12:34:43 pcdigigi kernel: [ 2685.849922] sd 4:0:0:0: Attached scsi generic sg2 type 0
Jan 28 12:34:44 pcdigigi kernel: [ 2685.953392] sd 4:0:0:0: [sdb] Write Protect is off
Jan 28 12:34:44 pcdigigi kernel: [ 2685.953398] sd 4:0:0:0: [sdb] Mode Sense: 03 00 00 00
Jan 28 12:34:44 pcdigigi kernel: [ 2685.953700] sd 4:0:0:0: [sdb] No Caching mode page found
Jan 28 12:34:44 pcdigigi kernel: [ 2685.953705] sd 4:0:0:0: [sdb] Assuming drive cache: write through
Jan 28 12:34:44 pcdigigi kernel: [ 2685.955504] sd 4:0:0:0: [sdb] Attached SCSI disk

The libmtp9 are the version 1.1.8-1+b1.