I would nt recommend resetting the router.
Please follow the steps on a computer connected to the router so as to check the network key:
1. Open the browser(Internet Explorer or Mozilla Firefox).
2. Access the router usually http://192.168.0.1
else try http://www.routerlogin.com
3. Login to the router with the Username as admin and password as password (unless you have changed it).
4. Click on Wireless Settings'(under Setup) from the left menu.
5. Check if 'WEP (Wired Equivalent Privacy)' or 'WPA-PSK (Wi-Fi Protected Access Pre-Shared Key)' is selected under 'Security Options'.
6. If WPA-PSK is selected, copy the code entered in the passphrase.
7. If WEP is selected, copy the code entered in the key that has been checked.
This is the code required for connecting the wireless computer to the
routers' wireless network.
In some cases, for security reasons the passphrase might show as asterisks. In this case type a new password and click apply. You will then have to use the same password for all the wireless devices connecting to the network.
I hope this information allows you to resolve this issue.
If I have helped you, please help me, and rate this suggestion the highest FixYa rating. If you cannot rate this post with the highest rating, then please comment to this post and I will try to help you further.