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header checksum error



We are running into a lot of server timeout when sending mails, I download wireshark to check the probelm on running the program i got this error

Internet protcol,src Dsy header checksum 0x0000 [incorrect,should be 0x3cf4 , what does this mean? we are behind a check point firewall and a cisco asa5510 firewall


asked 07 Feb '11, 08:34

jwc1972's gravatar image

accept rate: 0%

One Answer:


It means that you probably used Wireshark to capture your own traffic on your local machine. Outgoing packets will most likely show incorrect checksums due to checksum offloading, especially since yours is 0x0000. See

Meaning: what you found is not a problem, it's a result of your capture setup and not an error.

answered 07 Feb '11, 09:00

Jasper's gravatar image

Jasper ♦♦
accept rate: 18%