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Problem:
Slow browsing of machines on the network.
Slow Remote Desktop Connection.
How to turn off auto-tuning?
Slow when accessing network resources.
Fetching files from network folders is slow.

Cause:
Microsoft Windows Vista has auto-tuning enabled for TCP/IP which continually adjusts itself. It increases file transfer speed on the network but in some cases it may actually slow down everything which is accessing network. Auto-tuning also slows down network browsing of other machines on the network.

What is Auto-Tuning?
Microsoft TCP/IP stack supports Receive Window Auto-Tuning. Receive Window Auto-Tuning continually determines the optimal receive window size by measuring the bandwidth-delay product and the application retrieve rate. It adjusts the maximum receive window size based on changing network conditions. By default in Windows Vista Receive Window Auto-Tuning enables TCP window scaling which allows up to 16MB window size.
The TCP/IP stack monitors the connection and measures the current bandwidth delay for the connection and the application receive rate and adjusts the receive window size to optimum throughput.

Solution:
To disable auto-tuning:
Run command prompt as an Administrator.
Type: "netsh interface tcp set global autotuninglevel=disabled" (without quotes) and press enter.

You may also need to run this command:
netsh interface tcp set global rss=disabled

To enable auto-tuning:
Type: "netsh interface tcp set global autotuninglevel=normal" (without quotes) and press enter.

To view the current TCP settings:
Type: "netsh interface tcp show global" (without quotes) and press enter.

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