I don't know my security key!! - D-Link ADSL2/2+ Modem/Wireless Router 4-Port Switch, 802.11g, QoS (DSL-2640B)

Look on the underside of the Router. it is usually marked on there. look for a WEP or WPA with a number.

The security light means the computer is not reading the chip in the key.
You should have a sensor in the key lock and a chip on the key programmed for the security system.
I would try a spare key first. If you don't have one, you can get one from the dealer or some locksmiths.
If you know you have a good key, the problem may be with the sensor in the lock cylinder.

try to download your keys or entire gold pack to www.piratebay.org or www.kickasstorrent website.....

As long as you still have one that works, it's easy.
1) Insert the "original" (working) Key.2) Turn the Ignition to ON (RUN), but do NOT start the engine. Turn the Ignition OFF and remove the key.3) Within 15 seconds insert the new key and turn the Ignition to the ON (just to ON, not to START) position. The Security indicator should light up for about 2 seconds to indicate that the new key has been programmed.
At that point, it should work. I don't know how many different keys you can get the Theft Deterrent Module to recognize; there may be a limit.
If you're don't have a working key now, it's much more time-consuming;the procedure to get the TDM to recognize a different key takes about 30 minutes when you don't have an old one that works.

There is not a default key store password.
You can go to Options >Security Options>Key Stores.
You may be given an opportunity to enter and confirm a Key Store Password. If you are, do it and you'll be fine.

The network security key for a router is typically the router serial number... just look at the label on the bottom or side of the router. If that doesn't not work, call your carrier for information about what security key they used.

1. At the Setup screen, tap "Nintendo Wi-Fi Connection Settings."
   
2. Tap "Connection 1 None."
   (Don't see "None" for Connection 1? To ensure any existing settings don't interfere with getting connected, tap the button, then choose "Clear Settings.")
3. Click on "Search for an Access Point."
   
4. The Nintendo DS will search for any wireless networks within range. Once it is finished searching, it will display the names of all the wireless networks it finds.

Once you have done this you may find next to your wi-fi, a lock this is what they mean:

No security - Your wireless network is unlocked.

1. Tap on your network name to select it.

1. Select "OK," "Save Settings," and then "Yes." The Nintendo DS will run a connection test with your wireless router.

• The connection test was successful - Your Nintendo DS is now connected online and you can enjoy the Nintendo Wi-Fi Connection features of the game!
• The connection test was not successful - If the test was not successful, you will receive an error code.
  
  • Error Code 51300: This means the security code or network name entered into the Nintendo DS is not the same one the router is set to. To reach your connection settings, click "back" on the error code screen. Make sure to pay extra attention to the security key you find in your router's settings and enter it exactly as it appears (the key is case sensitive).
  • All other error codes: Try our error code lookup where we have detailed information on many common error codes.

WEP security - Your wireless network is secured with WEP and requires a security key.

1. Enter your router's WEP key into the Nintendo DS Don't know your router's security key? Let us help you find your router's security key. Select the brand of your router below and we'll provide you with the default information for that brand! Linksys Netgear DLink Belkin Apple 2Wire All other brands Enter your WEP keyOn the upper screen you will be informed that "A security key is needed to connect to this access point." Enter your security key by tapping the empty field, and select "OK" when finished.
   

1. Select "OK," "Save Settings," and then "Yes." The Nintendo DS will run a connection test with your wireless router.

• The connection test was successful - Your Nintendo DS is now connected online and you can enjoy the Nintendo Wi-Fi Connection features of the game!
• The connection test was not successful - If the test was not successful, you will receive an error code.
  
  • Error Code 51300: This means the security code or network name entered into the Nintendo DS is not the same one the router is set to. To reach your connection settings, click "back" on the error code screen. Make sure to pay extra attention to the security key you find in your router's settings and enter it exactly as it appears (the key is case sensitive).
  • All other error codes: Try our error code lookup where we have detailed information on many common error codes.

WPA security - Your wireless network is secured with WPA and requires a security key.
The Nintendo DS and Nintendo DS Lite are not compatible with WPA security. If you would still like to connect your Nintendo DS online, you will need to either change your router's security to WEP, or disable security entirely. Please note that any changes you make will affect other devices that connect wirelessly to your router.

It means: Unable to connect to your wireless network


Likely cause: It appears that the security settings entered into the Nintendo DS are not the same as what your wireless router is set to allow.


How to fix: Make sure the security key and security type are entered into the Nintendo DS exactly as they appear in your router's settings.

Don't know how to find your router's security key?

http://www.nintendo.com/consumer/wfc/en_na/ds/results.jsp?error_code=051300&system=DS&locale=lang

I have never heard of this problem. I didn't know they HAD security keys. It is likely referring to your network security key. Depending on the setup, your key can be located in different places. In most cases, however, it is on a sticker on the router somewhere, under the heading WEP key or something like that.

Welcome to fixya

No proplem you don't need a software cd to secure the router. Please follow the steps

Click the below link
http://192.168.1.1

Now it will ask for username and password

Enter username = ( blank) and password = admin
If you can't login using this credentials then you will have to reset the router

If you logged in . Then click on Wireless > Wireless security

On this screen select

Security Mode : WPA Personal
WPA Algorithm : TKIP
WPA shard Key : "enter a password here"
Group Key Renewal : set to default

Click on save settings. After that restart router .
Now your wireless network is secured and you will have to type the WPA shared key inorder to connect to router when it prompts

Thanks

Vote me If it helps