I have the sign-in password, but I don't have the password to access the router to change the sign-in password... I need to do this because someone has the PW that should not.
I need to know, if I reset the router with the reset button, do I need to reconnect the router to my PC through ethernet cable to reconfigure it, or can I simply let my wireless adapter find it again and start from there?
I do not have the disc... I do not have an ethernet card on my PC. This router was initially setup by an old roomate.
It is possible to configure the router through a wireless link although it is not recommended as you can never be sure whether you connect to your wireless router or your neighbor's Linksys router.
Therefore, the initial configuration of the router should always be made through a wired connection. Configure the wireless SSID and wireless security settings. Afterwards you can be sure that it is your router when you connect to your SSID with your passphrase/key.
If you don't have an ethernet port on your computer (pretty rare nowadays as the ethernet adapter is often onboard on the motherboard) you have to take whatever hints you can get to see whether you are connected to your router or not.
First, I would suggest to turn off the router (unplug from power). Scan the neighborhood with your wireless computer for other networks. Do you find any networks named "linksys"? You should also try to connect manually to a network named "linksys" with no encryption in case someone is running a Linksys router with default settings but with SSID broadcast disabled.
If you cannot find any "linksys" network and you cannot connect manually to any either chances are pretty good that there are no routers with this SSID.
Next, plug in your router. Press the reset button for 30 seconds and observe the lights to be sure that it is resetting (in case the reset button is just broken...). Now scan for wireless networks again. You should find a network "linksys" with no encryption.
If you have found another "linksys" network before you have to be double careful to connect to the correct router. If you have connected to a "linksys" network before, disconnect first. Place the computer right next to the router, then let the computer scan and connect to the "linksys" wireless network. Look carefully at the lights on the router. The WLAN should be flashing if there is something transmitted to and from the router (I don't know if this is the case for all routers, though). If it is flashing right when you are connecting you have a good chance that it is connecting to your router.
The computer should get an IP address from the router. Point your browser to http://192.168.1.1/, click on the wireless tab. Change the SSID/network name from "linksys" to something unique. Save the setting.
After the router changed the settings and possibly rebooted, you have to connect your computer to the new SSID. Again, check the lights on the router if they suggest that you are really connecting to your router and not somebody else's.
Go to http://192.168.1.1/ and configure the security settings on the wireless security subtab. After you have saved the settings the computer will loose the connection again.
Scan again for your new SSID and connect manually. The computer should now ask for the encryption key and then connect successfully.
Afterwards you should remove the "linksys" SSID from the list of preferred networks on your wireless connection to prevent the computer to connect accidentally to somebody else's router.
After you have setup the router with wireless security don't forget to change the default password "admin" for the web configuration interface on the Administration tab.
Verify once more that you have actually reconfigured your router and not somebody else's. Unplug your router from power. Scan with your computer for networks. If the computer still finds your new SSID and connects you have obviously configured the wrong router. In that case you have to start over with the configuration connecting to the next "linksys" network available. Eventually you should change your router.
Otherwise, if your new SSID disappeared with the powered down router and reappears after you plug it back in, it suggests very much that you are indeed connecting to your router and not somebody else's.
If you have to configure the router for your internet connection you can do so now. Be sure to do this after you have correctly identified and connected to your router. You don't want to enter your DSL credentials (if you have any) on somebody else's router.