unknown device problem

Reboot the computer and see if it  goes away. There was a major update to windows 10 in preparation for the anniversary update on Aug 2. If the computer is working OK, you can ignore the unnecessary device drivers. If some hardware is missing drivers, visit Dell Support Downloads and Drivers to check for updates.

Here is some info-- www.reddit.com/.../

Make sure the following are installed.

Intel Chipset Driver:

http://downloads.dell.com/FOLDER03215014M/1/Chipset_Driver_39M09_WN32_10.1.1.7_A00.EXE 

Intel Management Engine Interface:

http://downloads.dell.com/FOLDER03431034M/1/Chipset_Driver_HHFF4_WN32_11.0.0.1166_A02.EXE 

Intel Dynamic Platform and Thermal Framework:

http://downloads.dell.com/FOLDER03757117M/1/Chipset_Driver_NWWR5_WN32_8.2.10900.330_A03.EXE 

Intel HID Event Filter Driver:

http://downloads.dell.com/FOLDER03443443M/1/Chipset_Driver_J1KG5_WN32_1.1.0.311_A01.EXE 

Intel Dynamic Platform and Thermal Framework Driver:

http://downloads.dell.com/FOLDER03513692M/5/Chipset_Driver_C0NNV_WN32_8.1.10605.221_A01.EXE 

Intel Virtual Buttons Driver:

http://downloads.dell.com/FOLDER03215107M/1/Chipset_Driver_WPRVY_WN32_1.1.0.21_A00.EXE 

Intel Rapid Storage Technology:

http://downloads.dell.com/FOLDER03707771M/1/Serial-ATA_Driver_PFJ82_WN32_14.8.9.1053_A06.EXE 

FreeFall Sensor:

http://downloads.dell.com/FOLDER03215297M/1/Application_XY9JX_WN32_4.14.65_A00.EXE 

Realtek Card Reader:

http://downloads.dell.com/FOLDER03215165M/1/SD-Card_Driver_JJP10_WN32_10.0.10125.31214_A00.EXE 

Intel Video:

http://downloads.dell.com/FOLDER03713651M/1/Video_Driver_V4TPP_WN32_20.19.15.4454_A07.EXE 

Audio:

http://downloads.dell.com/FOLDER03453649M/1/Audio_Driver_H044Y_WN32_8.65.122.0_A03.EXE 

Dell Quickset:

http://downloads.dell.com/FOLDER03215285M/1/Application_MVW09_WN32_11.1.32_A00.EXE 

I did reboot many times and installed all updates. It didn't helps.