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NPF driver can’t start “System error 31”


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 !!

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asked 07 Dec '15, 22:18

Biigg%20Sakun's gravatar image

Biigg Sakun
accept rate: 0%

One Answer:


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.

answered 11 Apr '16, 17:36

Yang%20Luo's gravatar image

Yang Luo
accept rate: 4%