If you didn't write it down, go to the management page of your router (that's where you set it begin with) and see what it says. It might tell. Or - depending on the router - it might only shows stars or dots. In that case, type a new one, and change all your wireless devices to use the new one.
And it makes sense to write it down somewhere this time, but by now you've understood that, I think.
Kees
How can I find out what my WPA passwod is.

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