Fix large file copying problems in Windows Vista

Out of the box Vista can have some issues with large file transfers over a network. This is because of a new Vista feature called 'receive window auto-tuning'. In a nutshell, this allows Vista to automatically scale the size of each packet of data it requests and receives over a network connection to suit the available bandwidth. This is a good thing. However, older networking hardware may have issues with this newfangled technique and refuse to co-operate, leading to dropped file transfers, slow performance and other weirdness.

If you are experiencing network issues with large file transfers and occasional connection problems with applications like Messenger, we recommend that you restrict or disable the receive window auto-tuning feature.

To do this, open a command prompt window with administrative privileges.

Type 'netsh interface tcp set global autotuninglevel=restricted' and press Enter.

If this fixes your issues, relax. If you continue to have networking problems, open another administrative prompt and type 'netsh interface tcp set global autotuninglevel=disabled'.