Using this registry DWORD value – TcpWindowSize  in HKEY_LOCAL_MACHINESYSTEMCurrentControlSetServicesTcpipParameters to change the default TCP Window Size does not seem to improve the perfromance of the throughput. It seems this reg key doesn’t work any more.

https://learn.microsoft.com/en-us/troubleshoot/windows-server/networking/description-tcp-features#tcp-window-size 

​Using this registry DWORD value – TcpWindowSize  in HKEY_LOCAL_MACHINESYSTEMCurrentControlSetServicesTcpipParameters to change the default TCP Window Size does not seem to improve the perfromance of the throughput. It seems this reg key doesn’t work any more.
https://learn.microsoft.com/en-us/troubleshoot/windows-server/networking/description-tcp-features#tcp-window-size   Read More

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