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I have worked with WinPcap site with no luck when I try and install WinPcap native or through Wireshark I get a message it is already installed when this is a new win 7 install.

I can see that others have had this problem but I see no solutions?

I have a network down and need help


asked 16 May '12, 09:05

melliott-aerohive's gravatar image

accept rate: 0%

edited 16 May '12, 13:13

Guy%20Harris's gravatar image

Guy Harris ♦♦

  • What version of Winpcap did you try to install (maybe the version you tried is not supported on windows 7 (64bit)?
  • What is the output of this command:

    runas /user:administrator sc qc npf

  • What version of Win7 (32/64 Bit, SP1) is installed?
  • Does this file exist on your system: system32/drivers/npf.sys?


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answered 16 May '12, 09:58

Kurt%20Knochner's gravatar image

Kurt Knochner ♦
accept rate: 15%

edited 16 May '12, 10:38

Win 7, 64bit, SP1

Yes there is a npf.sys and npfs.sys

(16 May '12, 10:39) melliott-aer...

on a clean system?

(16 May '12, 10:43) Kurt Knochner ♦

except for a failed wireshark install yes

(16 May '12, 11:27) melliott-aer...

OK, my network is dead and I really need to capture some packets to find out what is going on.

Is there anyway to get pcap loaded on a new win 7 sp1 64bit machine where it keeps saying there is already a version running when the only thing I have loaded is wireshark that gave me the initial failure to load pcap.

I can't believe that this should be so hard on an state of the art machine

(16 May '12, 21:07) melliott-aer...

you did not provide the output of

runas /user:administrator sc qc npf

If you want help, you need to give information ;-)

(17 May '12, 00:32) Kurt Knochner ♦
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question asked: 16 May '12, 09:05

question was seen: 5,720 times

last updated: 17 May '12, 00:32

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