Whenever the laptop connects (or automatically connects on start-up) to a wireless network, Windows completely hangs (screen freezes; mouse and keyboard has no effect; CtrlAltDel has no effect), and it is necessary to force a shutdown by pressing the power button for 5 seconds.
It also has a few other issues, including taking a long time to start up, despite having only the usual programmes installed when buying from a computer shop.
I was going to attempt to install Windows 10, but I then realised that you need to install updates to upgrade for free, which obviously cannot happen while Windows refuses to connect to any wireless network.
I would tell my friend (an elderly lady) to take it back to the shop, but it is no longer covered by the original guarantee (she bought it over 1 year ago). She bought it from PC World (in the UK), if that's any help.
The laptop is a Lenovo G500 (Windows 8.1 Home N) with a 2.4 GHz Intel Pentium Inside processor, 4 GiB installed RAM, and only the default drivers installed. No extra applications, other than the ones it came installed with, and has not been used much.
Any ideas on what the problem could be, or how to get a free update to Windows 10?