The first thing I'd do would be to check for an updated driver for your
network adapter, things like this are typically driver faults.

First I'd have a look in Windows Update within the Control Panel to see if
there's an optional driver related to Wi-Fi, if there is install it and see
if it fixes it.  If there isn't a driver there, you'll need to do a bit of
manual leg work.

Two ways to proceed from here, check on the computer manufacturers website
to see if they have a newer driver listed, or look at the network adapter's
manufacturer's website to see if they have one.  To do this you'll need to
identify the network adapter, to do that go to the Device Manager, the
fastest way to launch it would be from Start Search, just type in device
manager and it should show up.  Expand Network adapters and it should be
listed.