Fix for poor network performance in Windows Vista

If you experience slowdowns or poor network performance in Windows Vista like slow browsing performance occasionally or all the time you might use a router or network device that is causing problems for Microsoft’s Receive Window Auto-Tuning Level. It’s not the routers fault or your fault but more something that is caused by how the new feature was implemented into Windows Vista.

The fix is rather straightforward, you need to run several commands in the command line as an administrator. Start with netsh interface tcp show global which displays the TCP Global Parameters. One parameter listed is called Receive Window Auto-Tuning Level which can be restricted, disabled, normal or highlyrestricted and probably several other that are not that important for the solution.

The command netsh interface tcp set global autotuning=disabled disables auto tuning which should lead to a speed increase if your computer experienced slowdowns and connection errors. Setting autotuning=normal returns to the default state for the autotuning parameter. Some suggest to set autotuning=restricted before disabling it fully or to autotuninglevel=highlyrestricted.

I would begin with restricted, if that does not help I would change to highlyrestricted and if that does not have the desired effect I would disable the feature completely.