Laptop stopped connecting via wifi but what's happening doesn't make sense.

[#1]

Bit of a strange problem. My sister's laptop suddenly stopped connecting to her router via wifi. Nothing has been changed on either the laptop or the router for over 6 months. The router seems fine - phones, tablet and a PC are connecting with no problem. Brought the laptop to my house and it won't connect to my wifi either. After doing diagnostics, tests etc we took the laptop back to PC World and it connected ok to their wifi!! They couldn't explain it and suggested doing a factory reset, which I did, but it still won't connect to either network. The only common factor is we both have Plusnet. So I'm at a loss to explain how the laptop can connect to PC World's wifi network but not to either of our home networks. Does anyone have any ideas? Thanks.

ps: it connects ok using ethernet cable.

[#2 · Accepted solution]

UPDATE: I've just tried something I read in another thread. Seperating the 2.4 and 5ghz wifi frequencies did the job 😀 Still dunno why the problem suddenly appeared though, but glad it's sorted.

[#3]

• Go to Your computer and Press the Windows Key + R Together on the keyboard.
• Type ncpa.cpl and press Ok Or You can Go Manually Go to Control Panel >Network And Internet>Network & Sharing Center >change adapter Settings>Select Your Current WiFi Network Adapter
• Right Click on it and Go to the Properties then Under the WiFi adapter Settings Please Click on configure
• Go to the Driver and Hit on Update Driver and you may see a new Box with 2 Options.
• Click on Search Automatically for updated Driver Software and Get an auto-update.
• You can also manually install the driver if you want to use the 2nd option. for that, you may need to download the wireless driver from the official laptop manufacturer website and then upload it using the second option.

Source:- Fix WiFi Disconnecting 

[#4]

Thanks for the reply Varonik, but this problem was solved 4 months ago (see above) and it wasn't down to a driver update.