iPhone 3G iOS4 Wifi not working while iPhone 3G iOS3 is working.

I was using the iPhone 3G mobile phone with iOS3 then I upgraded my iPhone with the version iOS4 after which the Wifi of my mobile phone has stop working. When I was using the iOS3 on my mobile phone then the Wifi used to work properly. I don't know what is wrong with my mobile phone so I need a proper solution about how I could get fix with my Wifi problem.

I am also facing the same problem in my iPhone 3G and my phone wifi used to work fine with the version 3 till I upgraded it for which I got lot of search to solve the problem but it was found that the Wifi was not working due to the software problem and to get fix with the Wifi problem you need to get the update or any patch for your mobile phone software.

My friend has downloaded the version 4 for his iPhone 3G and after that he found that his mobile phone has started to work slow and he was not able to find the working of his Wi-Fi. He was not able to find any solution for the his problem so he just downgraded his iOS after which again he was able to use his Wi-Fi and also his mobile phone was working faster.

It seems that the upgrade iOS4 is not done on your mobile phone properly for which its not been supported by your mobile phone. So you have to make sure that the upgrade which is done should be upgraded from the official website of the Apple and also make sure that the software for the Wifi should be updated. You can also get the upgrade of the iOS4 by jailbreaking of the mobile phone.