I’ve already got three computers happily using my home wifi network.
I just bought a new laptop. It can see my router, but asks for the network password before allowing Internet access.
I thought I’d written down this password, but apparently something is wrong, since the password doesn’t work.
Can I get a computer already connected to reveal the password?
If so, how?
Thanks for your help!
As always, what OS are you using?
It’s not the computers where you should be looking; the easiest place to find your settings including the WEP or WPA key (“password”) is the router. Which may itself have a login password, hopefully you have that, then just navigate to the the wireless settings.
ETA: And the router itself is usually accessed through its web service at a specific local IP address, often something like 192.168.1.1, but different brands and models differ.
Windows 10
On Windows you can use one of your connected machines to find the password, see instructions here:
Write the password on a piece of tape and afix to the bottom of the router once you figure it out. If you can’t determine the the existing password, there’s usually a reset button to knock the router settings back to factory default.
Thanks posters, I found my password. 
I used an older computer on the Network. I had to go through ‘Control Panel’ to find ‘Network + Sharing Centre’, but then ‘Security’ led me to the password.
Yes, it’s a good idea to have passwords attached to devices at home!
Most current routers also should support WPS, so that you don’t need to enter a password at all. When the password prompt appears, you can instead just push the WPS button on the router (depending on the model, a couple of seconds or until some light flashes or similar), and the connection will be set up automatically.
It’s not like writing your PIN on your debit card. Anyone that has access to the bottom of your wifi router is already deep inside your house. And don’t you share your wifi with guests already?
I didn’t think glee was being sarcastic.
Some routers include a small, hard-to-press button that will reset the router to its factory default SSID and password (e.g. “admin”), which are typically noted on its label, or can be found via an online search of the router model ID.
Note that using this scheme will require resetting devices that are currently connecting using the now-forgotten password.
I’m pretty sure all wifi routers have this ability. Though it might be more complicated than just pressing the button any time - google with the specific model number + “factory reset”.
Sorry if I gave the wrong impression. :o
I agree that within my house it’s vital for me to know my passwords - hackers aren’t going to see what I’ve written on paper.
Thanks again to all who replied.
I’m sorry for my negative misinterpretation and glad everything is up and running.