What is npf.sys?

npf.sys is part of WinPcap and developed by CACE Technologies, Inc. according to the npf.sys version information.

npf.sys's description is "npf.sys (NT5/6 AMD64) Kernel Driver"

npf.sys is digitally signed by CACE Technologies, Inc..

npf.sys is usually located in the 'C:\Windows\system32\drivers\' folder.

None of the anti-virus scanners at VirusTotal reports anything malicious about npf.sys.

If you have additional information about the file, please share it with the FreeFixer users by posting a comment at the bottom of this page.

Vendor and version information [?]

The following is the available information on npf.sys:

Product nameWinPcap
Company nameCACE Technologies, Inc.
File descriptionnpf.sys (NT5/6 AMD64) Kernel Driver
Internal nameNPF + TME
Original filenamenpf.sys
Legal copyrightCopyright © 2005-2010 CACE Technologies. Copyright © 1999-2005 NetGroup, Politecnico di Torino.
Product version4.1.0.2001
File version4.1.0.2001

Here's a screenshot of the file properties when displayed by Windows Explorer:

Product nameWinPcap
Company nameCACE Technologies, Inc.
File descriptionnpf.sys (NT5/6 AMD64) Kernel Driver
Internal nameNPF + TME
Original filenamenpf.sys
Legal copyrightCopyright © 2005-2010 CACE Technolo..
Product version4.1.0.2001
File version4.1.0.2001

Digital signatures [?]

npf.sys has a valid digital signature.

Signer nameCACE Technologies, Inc.
Certificate issuer nameVeriSign Class 3 Code Signing 2004 CA
Certificate serial number489613e7dd6964b152a4e8f71813e76a

VirusTotal report

None of the 51 anti-virus programs at VirusTotal detected the npf.sys file.

None of the 51 anti-virus programs detected the npf.sys file.

Filename variants

npf.sys may also use other filenames. The most common variants are listed below:

Folder name variants

npf.sys may also be located in other folders than C:\Windows\system32\drivers\. The most common variants are listed below:

Other files also named npf.sys

npf.sys (41 votes)

Hashes [?]


What will you do with npf.sys?

To help other users, please let us know what you will do with npf.sys:

What did other users do?

The poll result listed below shows what users chose to do with npf.sys. 12% have voted for removal. Based on votes from 25 users.

User vote results: There were 3 votes to remove and 22 votes to keep

Malware or legitimate?

If you feel that you need more information to determine if your should keep this file or remove it, please read this guide.

Please select the option that best describe your thoughts on the information provided on this web page

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Please share with the other users what you think about this file. What does this file do? Is it legitimate or something that your computer is better without? Do you know how it was installed on your system? Did you install it yourself or did it come bundled with some other software? Is it running smoothly or do you get some error message? Any information that will help to document this file is welcome. Thank you for your contributions.

I'm reading all new comments so don't hesitate to post a question about the file. If I don't have the answer perhaps another user can help you.

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