Something new. Reported to help a lot, especially with Internet connections higher than 10Mbps.
Basically, we browse here in the registry:
Computer\HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\LanmanServer\Parameters
we create (or edit) DWORD IRPStackSize, and we set it to 32. Default is 15, and Microsoft reportedly says that values 33-38 are fraught with peril.