Windows 7 tcpip.sys Auto Patcher to Increase TCP Connection Limit

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TCP-Z Free Download (Half Open TCP/IP Memory Patcher for x86 and x64 Windows 7

The powerful and all Windows versions TCP/IP (tcpip.sys) auto patcher, TCP-Z, has been upgraded to version 2.4 Build 20090108 to fully support Windows 7 Beta with build version 7000 (6.1.7000.0). The latest version of TCP-Z supports both 32-bit and 64-bit (x86 and x64) of Windows 7 Beta to patch the tcpip.sys and increase the limit imposed on concurrent half-open outbound TCP connection attempts.

TCP-Z V2.4.0.46 Build 20090108 Direct Download Links
Download Link 1:

Download Link 2:

Windows 7 Beta has the tcpip.sys file with version of 6.1.7000.0 (winmain_win7beta.081212-1400). By default, the TCP/IP half open connection limited value is 10. The patch is required to increase and optimize P2P networking such as BT speed, and to avoid or fix Event ID 4226 from occurring in the system.

Changelog for TCP-Z 2009.01.08 V2.4.0.46

+ Windows 7 x64 6.1.7000.0 Memory Patch.
+ GUI program, support keyboard control: Ctrl + Tab = switch tab; Tab = switch control.
* GUI program, File Patch, improve compatibility of disable WFP in Windows XP. Thank BRD-IlLusioN-CCCP.
* GUI program, fixed, user interface in non-standard DPI can not correctly display.

Source: My Digital Life


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Experiment. Its a free world. With modern connection speeds, the patch will make very litle difference.

From Microsoft :
"Limited number of simultaneous incomplete outbound TCP connection attemptsâ€â€￾ The TCP/IP stack now limits the number of simultaneous incomplete outbound TCP connection attempts. After the limit has been reached, subsequent connection attempts are put in a queue to be resolved at a fixed rate. Under normal operation, when applications are connecting to available hosts at valid IP addresses, no connection rate-limiting occurs. When it does occur, a new event, with ID 4226, appears in the system’s event log. What works differently? This change may cause certain security tools, such as port scanners, to run more slowly. How do I resolve these issues? Stop the application that is responsible for the failing connection attempts."

10 half-open simultaneous/concurrent connection are more than are needed, even for P2P. This limit is a rate limiter, not a connection limiter. You can have tons of half-open connections. Aletering this figure 10 will make it seem like you have a download speed increase. Fact is the simultaneous downloads are sharing the speed and the end result will be the same.

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