Hi I want to know how I can check my password on my wireless rouder.
I had someone install it from a store and I wasn't availabel so he had given
My password to my sister but she doesn't remember it what should I do?

There is a site that will help you find the default password of routers. It's at Default Router Passwords - The internets most comprehensive router password database . You need to know the IP address of your router. The default IP is usually set as 192.168.1.1 . Try typing that IP address into the address bar of your browser. If it a username and password page comes up you are at your router. You can also type ipconfig /all at the command prompt and find your router's IP address. It will be listed as the default gateway. Now, use the website and try the default username and password. If that doesn't work, the only other thing I know to do is contact the manufacturer's technical support line. They may be able to walk you through resetting the password back to default.

If the Default passwords fail, you can just reset it

There is usually a small hole in the back that has a small button behind it(some times they are marker "Reset") use a paper clip or other small pointy object and press the button.

For best results unplug the device and press and hold the button for 5 seconds if that fails you can try pressing and holding the button while you plug it in, this is usually the method for older D-Link routers.

Be warned that this will reset all the settings as well, including SSID's, and security keys, Firewall rules. But if its just a wired router then there is usually no problem because the default settings work.

You just need to access the router setup page and there you can find all the settings of your router including the wireless security...

OH ,I get it

Its always recommended that you should connect a cable while accessing router setup page, So your computer and wireless router should be hardwired.
Enter the desired default gateway and login
You can find all your default router passwords depending on the model.

Once you get connected to your wireless network. Go to wireless network setting then click on edit there you will be able to see the existing details if the password displayed is in encrypted form just uncheck the hide characters option.
Now you are able to see the existing password.

Hi,
Its very important to have your network secured and for this you will need to keep it safe with a password and its very important to know how to do it.
That's why I am sharing this link: How would I find out what my password is Wireless router? | Techyv.com

Here is another which will help you more to understand the situation: How to protect wireless network ? | Techyv.com

Here is another link which I found on google: How do I find out what my forgotten network key is so I can add a laptop to our wireless network?