This is our old Q&A Site. Please post any new questions and answers at

I have tried every online solution , run as admin, re-install the npf.sys appears in windows/system32/driver and msinfo>software environment>system drivers>npf but the driver can't be start there is no NetGroup Packet Filter Driver in my Device manager>Non-Plug and Play driver

really need help with this !!

alt text

asked 07 Dec '15, 22:18

Biigg%20Sakun's gravatar image

Biigg Sakun
accept rate: 0%

SYstem error 31 means:


31 (0x1F)

A device attached to the system is not functioning.

It's very obscure to understand what it actually means.

You can try Npcap:, it is a fork based on WinPcap and have built its own drivers. So it will possibly solve your issue.

permanent link

answered 11 Apr '16, 17:36

Yang%20Luo's gravatar image

Yang Luo
accept rate: 4%

Your answer
toggle preview

Follow this question

By Email:

Once you sign in you will be able to subscribe for any updates here



Answers and Comments

Markdown Basics

  • *italic* or _italic_
  • **bold** or __bold__
  • link:[text]( "title")
  • image?![alt text](/path/img.jpg "title")
  • numbered list: 1. Foo 2. Bar
  • to add a line break simply add two spaces to where you would like the new line to be.
  • basic HTML tags are also supported

Question tags:


question asked: 07 Dec '15, 22:18

question was seen: 1,350 times

last updated: 11 Apr '16, 17:36

p​o​w​e​r​e​d by O​S​Q​A