When trying to reset router and reset it up;

If you are talking about the password to log in and make changes to router settings, according to the user manual for this router, found HERE, the default password is no password, in other words, leave it blank. If that doesn't work that means someone put a password on it and you will need to reset the router in order to log back in and make changes. If you need help with that, refer to the manual, or reply back to this message and I will help walk you through it.

I assume you're trying to login to the admin section to set up your router.

Most routers by default use (username, password):
admin, admin
admin, password
admin, (blank)

If your router has already been setup, but you forget the password, then you can try resetting.
There will be a small button on the back panel of the router labeled "reset". It's quite small, you'll need to use a paper clip or the tip of a pen to push it.

Give the router a few minutes to reset itself and to power up again. It is not reset to factory default settings. Try logging in with the suggestions above.

Perform a hard reset by pressing the button behind the small hole (use a paper clip) as you power it on. That will reset the router to it's factory settings. From there you can log in with the default password. Of course, you'll to reconfigure it from scratch but at least you'll be in control again. Be sure to change the password to something more secure.
Also, some routers will allow you to deny configuration access from wireless clients.

Contact you ISP...they will give you either you IP address to log on to access the network settings or they will just give you the password over the phone.

this can be due to two reasons.
first if you are trying to sign in ... it is possible that someone has logged on with you id so yahoo is denying another logon attempt. sometimes trying to log on when yahoo messenger is also logged in at the same time gives this error message. seleting temporary internet files can also help.

otherwise if this message comes up when trying to make a new yahoo id .. it simply means it is taken by someone else so try some other id.

Contact the support system, then may solve it.

press reset button for 10 seconds then all settings are defaults.
you can access your router witrh following link
http://192.168.0.1 or
http://192.168.1.1

well resetting the button at the back of the router makes the router go to factory default settings.As such you need to configure the router once again as per your service provider's settings.If you already have the IP informations and the other informations.You can try to log into the router using the default IP of 192.168.1.1 which would take you to the router home page.You can configure the Router and save the same.Once done you should be good to go.

Since you already tried steps 1 thru 4, give steps 5 and on a try


Write down configuration information such as IP addresses, security keys, opened ports and services, etc., that you modified. (The default username is admin and the password is either password or 1234. Try these before resetting the router.)

1. Press the reset button on the back until the test light blinks. This takes about 10 seconds. (To avoid accidental resets, the small button is recessed. Use a pen or paperclip to access it.)
2. Release the button.
3. Wait for the router to reboot.
4. Log in with the default password. If the router was not cleared, try these additional steps AFTER the router has finished rebooting.
   
5. Unplug the router's power.
6. Press and hold the reset button. While the button is held down, reconnect router's power.
7. Continue to hold the reset button for 20 seconds after reconnecting the power.
8. Wait for the router to reboot.
9. Log in with the default password.

The default username for this router is "admin" without the quotes, and the password is blank (don't type anything.) If that doesn't work, it may have already been changed, in which case you can soft reset the settings to factory defaults by using the reset button on the back of the box.