Laptop suddenly cannot connect to wifi. What to do?

[Microsoft Windows]

My wife's laptop suddenly stopped connecting to our wifi network. Every other device in the house (2 desktop pcs and 2 phones) connects perfectly so the problem is obviously with her laptop and, I assume, with the in-built wireless adapter.I've tried several, brand new USB wireless adapters with the same results; cannot connect to this network. If it's not the in-built adapter that's faulty then it must be the settings that may have been changed as a result of a recent update?We've tried disabling and disconnecting the in-built adapter to, then, try the USB adapter on its own with zero result.

Continue reading...