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You aren't actually seeing port 0 traffic, you're seeing fragmented IP <br />
packets without a L4 header, which shows up as src/dst port 0 in &quot;show <br />
firewall log&quot; and such. 
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OK, if that is true is there any way I can find what on his computer is causing this? If there is no way to do I have no recourse except to blow away his computer and start all over again.
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This is a W-XP computer. Will IPSec allow me to block port 0 or will it say 'Invalid Port Number&quot;?
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So would this be the correct syntax to block outgoing port 0 for IPSeccmd.exe?<br />
<br />
IPSeccmd.exe -w REG -p &quot;Block TCP 0 Filter&quot; -r &quot;Block Outbound TCP 0 Rule&quot; -f 0=*:0:TCP -n BLOCK<br />
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Does this tool go into the registry and make/revise entries? What actually tells it outgoing versus inbound? Is it simply the word Outbound or is it the 0=* versus *=0? Trust(0) to unstrust(*) versus Untrust(*) to Trust(0)?<br />

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I have a partner who works on a web site with me. Very often he gets cut off the hosting web server because the server senses unauthorized pinging coming from port 0. I have tried blocking all outgoing pings using Windows Firewall, Zone Alarm ansd Shields Up but none of them allow me to block port 0. Does any one have any idea how I can block this port?
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I have a partner who works on a web site with me. Very often he gets cut off the hosting web server because the server senses unauthorized pinging coming from port 0. I have tried blocking all outgoing pings using Windows Firewall, Zone Alarm ansd Shields Up but none of them allow me to block port 0. Does any one have any idea how I can block this port?

How to block TCP port 0?

Transmission Control Protocol/Internet Protocol (TCP/IP) is the set of networking protocols that define end-to-end connectivity specifying how data should be packeted, addressed, transmitted, routed and received at the destination. This functionality is organized into four abstraction layers which are used to sort all related protocols according to the scope of networking involved.