Fix slow LAN transfer speed of files in Windows 7

Disable “Large Send Offload (LSO)”

Large Send Offload is a technique of improving network performance while at the same time reducing CPU overhead. Apparently it does not work very well, so it was suggested to disable it (ref MSDN).

Follow these steps:

• Open Start Menu, right-click on Computer and select Properties
• Under Control Panel Home located on the left side of the window click onDevice Manager
• You will get a list of all devices on your machine. Expand Network Adapters.
• Find your Network Card and double-click on it.
• Select Advanced tab. You will get a list filled with different options.
• Select Large Send Offload V2 (IPv4) and set the value to Disabled
• Do the same for Large Send Offload V2 (IPv6) if it is available
• Click OK

Disable Large Send Offload V2 on the other computer and everything will work as expected.


ref: http://www.howtosolutions.net/2013/06/fixing-slow-sending-or-receiving-of-files-through-lan-network-using-windows/