How to change router settings for BUffalo WCR-G54 wifi router? i can't access the URL: http://192.168.0.11.1 thanks!

The number you mentioned is not the correct one ( http://192.168.0.11.1 ) You will need to check the settings of the router.
Is there any computer connected to the router with the cable. If yes then check the IP address on that computer.the default gateway will be the IP address of the router. you will need to use that number to open the router set up.

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This is actually wrong: http://192.168.0.11.1

If your router is connected to your computer via ethernet cable you will be able to get the configuration page of the router.

Windows XP
1. Click start
2. Click run
3. Type cmd in the box and press enter
4. On the black screen type ipconfig and press enter
5. Look for the default gateway
6. Copy that and use that to access the configuration page using the internet explorer
7. Open internet explorer, type http://the default gateway you copied in the address bar of the internet explorer
ex: http://192.168.1.0

Windows Vista
1. Click pearl button (start in xp)
2. Click on start search box (run in xp)
3. Type cmd in the box
4. Right click the black icon up at the top
5. Click on run as administrator
6. Click on continue
7. On the black screen type ipconfig and press enter
8. Look for the default gateway
9. Copy that and use that to access the configuration page using the internet explorer
10. Open internet explorer, type http://the default gateway you copied in the address bar of the internet explorer
ex: http://192.168.1.0