Windows Registry Editor Version 5.00
[HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\Tcpip\Parameters]
"SackOpts"=dword:00000001
"TcpWindowSize"=dword:0005ae4c
"Tcp1323Opts"=dword:00000003
"DefaultTTL"=dword:00000040
"EnablePMTUBHDetect"=dword:00000000
"EnablePMTUDiscovery"=dword:00000001
"GlobalMaxTcpWindowSize"=dword:0005ae4c
And it can saveas Speed.reg (note:the version of the Windows registry editer V5.0 is giver in old OS u can chang when it is not work)
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