It is a good idea to change your network security key every once in a while. You should treat it just like a password.
Just so we’re on the same page: your network security key is the key/password/passphrase used to add new devices to your network. It is, for all intents and purposes, a “password” to join your network.
The first place you’ll want to change this security key is on your router. Once you’ve done that, you’ll then need to change the key on all devices that connect to your router. If you change it on your computers or phones first, you’ll have a hard time trying to connect to your router to change the setting there.
1. Change The Security Key On Your Router
Start by logging into the administration interface of your router. Do this by typing your router’s IP address into your internet browser. You will need to enter your router’s admin username and password.
The screenshot below shows how I would change the security key in my Linksys WRT100 RangePlus wireless router. Depending on your brand of router, your entire interface may look different. However, the general idea is the same. You want to look for the wireless security settings page in your router.
The setting you will change will be the pass phrase. It may be labeled Security Key or something along those lines. Just type the key you’d like into the corresponding text box, then save it.
2. Change The Security Key On Your Computer(s)
I have a tutorial for finding your security key on PCs and Macs right here. Once you find it, you can just type in the new network security key you set on your router in step 1.