TCP/IP has reached the security limit imposed on the number of concurrent TCP connect attempts

I get this warning in event viewer of the system.  I seem to go for periods where I cannot access a PC on the network and then it will just come back up.  This is the only thing in the logs I can find that might be relevant.

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war1Connect With a Mentor Commented:
Greetings, mkurtzhals !

Windws XP SP2 introduces a few new twists to TCP/IP in order to babysit users and "reduce the threat" of worms spreading fast without control. In one such attempt, the devs seem to have limited the number of possible TCP connection attempts per second to 10 (from unlimited in SP1). This argumentative feature can possibly affect server and P2P programs that need to open many outbound connections at the same time.

To change or remove the limit, you can use the following program:

Event ID 4226 Patcher -
A patching program for removing or changing the limit imposed on connection attempts in SP2. The patcher has the ability to restore tcpip.sys back to the original... Still, you might want to back up tcpip.sys, use it at your own risk. The author of this patch can be reached @

You can manually edit tcpip.sys file.

Best wishes!
By any chance are you using Norton AntiVirus 2006 on the PC's?  I recently had a problem like this and found out that NAV 2006 worm detection module was blocking lan traffic because it thought it was "under attack".  If this applies, look in the NAV 2006 Reports/Worm detection logs.  

In my case I was backing up from one pc on the local network to another pc.  The high activity triggered the false-positive in NAV.

We have not heard from you. Did any comment help you solve your problem? Do you have any more question? If an Expert helped you, please accept his/her answer above with an excellent or good grade.

Thanks, war1
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