Sneaky Microsoft just updated our Windows XP software to limit ports, according to these forums. See the following, I am not sure quite where the code modification as suggested below goes, unless possibly modifying your Network Card TCP/IP stack or whatever (I am a Newbie and no Techie):

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This FAQ is not yet complete nor up-to-date. This will be changed sometime ...
• What's this EventID 4226?
• Which effects does this limit have?
• How can I find out, if I'm affected?
• I read something, that it's possible to change limit via regsitry. Is that true?
• 50 concurrent, half-open connections is to less for me. Is it possible to get more?
• Which other parameters does exist?
• Which languages are supported?
• I have Windows 95/98/ME/2000/XP SP1. Will these get supported soon, too?

What's this EventID 4226?
The EventID 4226 means, that there are to many concurrent TCP connection attempts. A connection attemp is a query to a computer, if it accept the TCP connection or not. If the computer is for example no more existent, it will be waited for a few seconds, until a timeout occurs and the connection attemp get canceled.

Since XP SP2 there are only 10 concurrent TCP connection attempts possible, while in SP1 it has not been limited.

Which effects does this limit have?
Applications with many connection attemps may work bad or not at all. Even web browsers, eMail clients or antivir programs can be affected and might bring a long time of waiting. Also administrative diagnosticprograms in companies make problem. In short, there seems to be more problems than there is an advantage.

How can I find out, if I'm affected?
Just have a look at Start/Maintenance/Control Panel/Administration /Management/Eventview/System if there are entries with the event id 4226. If yes, minimum one time the limit has been reached

I read something, that it's possible to change limit via registry (TcpNumConnections). Is that true?
Unfortunately not. Because the concurrent connection attemp limit has nothing to with concurrent connections, this registry-key is useless. Unfortunately there is no registry-key, which would allow the user to change the concurrent connection attemps.
50 concurrent, half-open connections is to less for me. Is it possible to get more?

Yes! Just use as a Parameter /L=limit, where limit describes the new limit.
For example a 100 limit can be set with the command:
EvID4226Patch /L=100

Which other parameters does exist?
Not entered yet ...

Which languages are supported?
Theoretical every lange is supported. If not, please contact me!

I have Windows 95/98/ME/2000/XP SP1. Will these get supported soon, too?
Because the limit got introducted in XP SP2, the other operating systems are currently unlimited.

Exception: Windows 2003 Server seems to be limited as well since SP1 beta. An update will follow ...


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My problem is, I am not quite sure where or what to patch.