Since you forgot the security ket for the wireless network you need to access the router setup page using the a computer that is working fine with the router, On the internet exploreer address bar of the working computer type in 192.168.1.1 , then that should be asking you for a username and password, just leave the username blank and password is admin. If tha admin password didn't work try typing your commonly use password. If you're already on the setup page of the router, Just go to wireless tab then there's a wireless security sub tab there where you can find the security key that you need...
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Since you forgot the security ket for the wireless network you need to access the router setup page using the a computer that is working fine with the router,
On the internet exploreer address bar of the working computer type in 192.168.1.1 , then that should be asking you for a username and password, just leave the username blank and password is admin. If tha admin password didn't work try typing your commonly use password.
If you're already on the setup page of the router, Just go to wireless tab then there's a wireless security sub tab there where you can find the security key that you need...
Hope that helps...........