Xbox 360 E cant connect wireless

•Xbox 360 S console and black adapter: The Xbox 360 S console and the black Xbox 360 Wireless N Networking Adapter cannot use the 802.11n wireless protocol in combination with WEP or WPA TKIP encryption. If your router requires WEP or WPA encryption, your
console will try to connect to your wireless network using a slower wireless protocol such as 802.11b, 802.11g, or 802.11a.

•Use WPA2 if possible: The best wireless encryption to use with your Xbox 360 console is WPA2 with AES encryption.

Here is the link with more information

support.xbox.com/.../error-cant-connect-wireless-network-978945

You might need to change your wireless router settings. Here are some things you should know:

Xbox 360 S console: The Xbox 360 S console’s built-in Wi-Fi uses the 2.4 gigahertz (GHz) frequency band. If your router is broadcasting using another frequency, your Xbox 360 S console cannot connect to your wireless network. Check your router documentation
to find out how to set your router to broadcast at 2.4 GHz. If you want to connect using the 5 GHz frequency band, you will need to add the black Xbox 360 Wireless N Networking Adapter to your Xbox 360 S console.

Xbox 360 S console and black adapter: The Xbox 360 S console and the black Xbox 360 Wireless N Networking Adapter cannot use the 802.11n wireless protocol in combination with WEP or WPA TKIP encryption. If your router requires WEP or WPA encryption, your
console will try to connect to your wireless network using a slower wireless protocol such as 802.11b, 802.11g, or 802.11a.

Use WPA2 if possible: The best wireless encryption to use with your Xbox 360 console is WPA2 with AES encryption.

Wireless N router and a gray adapter: If you have an 802.11n or N type router and a gray Xbox 360 Wireless G Networking Adapter, configure your N type router to use a mixed mode; broadcast using a combination of wireless standard N and either B, G, or A.

For more information on these problems with connections I would like you to click these links

support.xbox.com/.../cant-connect-to-xbox-live-wizard

support.xbox.com/.../error-cant-connect-wireless-network-978945

You have a built in wireless system in the Xbox 360 Slim. What you need is a modem and router (prefer wireless since you already have WLAN on your Xbox 360) Install your router device and connect that to modem. On your Xbox 360, search for your router, here's
a guide on how to do that
support.xbox.com/.../cant-connect-to-xbox-live-wizard

Here's a link on how to reset factory deaults:
support.xbox.com/.../error-cant-connect-wireless-network.aspx

Are you an Xbox 360 S or E console with the built-in wireless? If so, I'd either stick with a wired connection or use an external wireless adapter for your console.

The built-in wireless is pretty terrible in regards to signal strength.