I don't know what to do or how to fix it anymore. Every time I turn on Wifi on my iPhone my internet stops working. It'll connect, but it won't be of any use. When I go to my computer, my internet of course doesn't work either. Only after I turn Wifi off on my iPhone does my internet signal return. This only happens with the iPhone. I have my PS3 hooked up to the same network and it works just fine when connected to the internet. This problem started happening after I updated to iOS 4. Also noticed that if I hit "Renew Lease" it works just fine.. after like 2 minutes of getting all the information it needs, but I shouldn't have to be doing that every time. Can anyone help me out here? Should I change some settings on my linksys router? If so, what are they.. cuz I'm stumped. Btw - it's a 16GB iPhone 3GS.