Windows Half-Open Limit Fix is an utility program wrote by Dmitry, a Russian, that cracks, hacks or patches the system’s tcpip.sys file, the main file that provides TCP/IP communication protocol to change the maximum number of concurrent half-open outbound TCP connections, or connection attempts.

Microsoft started to implement a upper-bound limit on number of simultaneous half open outgoing TCP connection attempts in Windows XP SP2 and all future and new versions of Windows in order to slow the spreading rate of virus infection and malicious program and reduce the ability for computer to launch DDoS or DoS (Denial of Service) attack.

In Windows XP SP2 and SP3, the maximum concurrent half-open connect attempt limit is 10, and remains the same in Windows Vista and other Windows OS. When the limit is hit, new connection attempt will be put into queue. The limit also causes consequences of slow Internet download as speed of connection established to external peer computer is restricted. The limit especially and critically affect use of P2P (Peer-to-Peer) file sharing programs such as µTorrent, BitComet, eMule and P2PTV such as TVUplayer, PPStream, TVants, PPLive and many more.

Half-Open Limit Fix patches and fixes the tcpip.sys to unlock, clean and remove this limit, by increasing the maximum limit of half-open connection attempts allowed. It is fully automated, and works on all versions of tcpip.sys released.

To apply the patch using Half-Open Limit Fix, follow these steps:

1. Unpack and extract the ZIP archive to any folder.
2. Run the Half-Open Limit Fix program, i.e. Half-open_limit_fix_2.8.exe.
3. Select a new value for the limit for concurrent half-open outbound TCP connections. Valid value range from 1 to 255 (FF).
4. Click on Add to tcpip.sys button.
5. Restart computer.

Download: Windows Half-Open Limit Fix v2.8

Source: Windows Half-Open Limit Fix Home Page