Can't register Blend v2 on Windows 7

Have problem with RedBear Blend v2.

In maintenance mode install the latest firmware for DAPLINK:

Have this text in DAPLINK drive:

# DAPLink Firmware - see
Unique ID: 109300003350ad1f0f30323934353254a5a5a5a597969905
HIC ID: 97969905
Auto Reset: 1
Automation allowed: 0
Daplink Mode: Interface
Interface Version: 0242
Bootloader Version: 0242
Git SHA: af16b1713e236cd4242714179cc2d6bbd2a7e385
Local Mods: 1
USB Interfaces: MSD, CDC, HID
Bootloader CRC: 0xbe284a3a
Interface CRC: 0xcf6e2769

Connect to Zerinth and get this log trying to register:

Loading settings...
Checking for updates...
[info] Starting device registration
[info] Burning bootloader...
[error] Can't burn bootloader! --> Can't find device disk! Have you mounted the DAP Link device?

In Device manager:

Portable Devices

Ports(COM & LPT
ECP Printer Port(LPT1)
mbed Serial Port(COM17)

Universal Serial Bus Controllers
mbed Composite Device
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I was able to register, create virtual machine, virtualize Blend 2 on my Windows 10 laptop, but not on Win 7. Is there any specific problem with win 7?