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Hello my name is Karan. I'm currently using windows 7 64-bit. npf.sys is there in drivers and winpcap is also installed in my laptop but whenever I try to start npf service in cmd it shows me the service name is invalid. so what should i do. I opened cmd in administrator mode still getting this output. please provide a solution for it. first i downloaded winpcap because I was not sure that it is installed but when I open the .exe file of it, it was showing that you have a newer version of winpcap installed so installation is aborted.

asked 30 Oct '16, 14:09

karan9537's gravatar image

accept rate: 0%

Can you please add to your question the exact command you are entering?

(30 Oct '16, 14:21) grahamb ♦

What does the Help -> About window in Wireshark report? (Please copy and paste the text, rather than trying to post a screenshot.)

(31 Oct '16, 03:59) grahamb ♦

You might run into difficulties if Wireshark encounters a different version of Winpcap than the one the is bundled in the installer.

I suggest the following steps:

  • Make sure that the extra version of winpcap is not used by any other application
  • If another application is using winpcap, please try to "synchronize" the versions
  • If it is not possible to align the winpcap versions it might be necessary to use a separate computer for network analysis.

In my opinion the best way to fix the version problem is:

  • Make sure that you download Wireshark from the original download site
  • Only use the latest version of Wireshark, as new versions occasionally fix security errors.
  • Remove all older instances of Wireshark, winpcap and usbpcap
  • Reboot. You should no longer find an npf service.
  • Install Wireshark and allow the Wireshark installer to deploy the accompanying version of winpcap
  • Given the current problems with the installer, I suggest to delay the installation of usbpcap until you really need it.

If something fails, the system event log and application event log often give important hints and return codes.

One last hint: Make sure, that you have administrative rights.

Good luck and good hunting

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answered 30 Oct '16, 14:39

packethunter's gravatar image

accept rate: 8%

Thx for the answer. I will try it and tell you the result

(30 Oct '16, 23:30) karan9537

thank you for the concern all of you. i renamed the packet.dll with packet.dll.old and wpcap.dll with wpcap.dll.old and sucessfully installed winpcap and driver is also started. thank you once again.

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answered 31 Oct '16, 12:36

karan9537's gravatar image

accept rate: 0%

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question asked: 30 Oct '16, 14:09

question was seen: 2,207 times

last updated: 31 Oct '16, 12:36

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