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Forget Wi-Fi networks As previously reported, some instances of this problem appear to be caused by repeated, failed attempts to automatically join certain wireless networks. The temporary solution is as follows:

1. Navigate to Settings, then select Wi-Fi
2. Tap the arrow next to each listed Wi-Fi network and tap Forget this Network
3. Go back to the Wi-Fi screen and manually join the desired network

Failing that, turn Wi-Fi off, then back on using the Wi-Fi settings screen and re-apply the aforementioned steps, or turn Wi-Fi off altogether.

Delete and re-install iPhone 1.1.1 update This fix is a bit more involved, but has proved effective for a number of users and may be more permanent. It involves deleting the iPhone 1.1.1 update file from your computer, then restoring your iPhone, forcing it download and install a fresh copy from Apple’s servers.

Follow these steps:

On a Mac Look in the directory ~/Library/iTunes/iPhone Software Updates and move the file iPhone1,1_1.0.2_1C28_Restore.ipsw to the Desktop or another location. Next, connect your iPhone to your Mac, and select the “Restore” option from within iTunes.

On a Windows PC Look in the directory C:\Users\Your name\Application Data\Apple Computer\iTunes\iPhone Software Updates\ or C:\Documents and Settings\username\application data\apple computer\itunes\iphone software updates\ and move the file iPhone1,1_1.0.2_1C28_Restore.ipsw to another location. Next, connect your iPhone to your computer, and select the “Restore” option from within iTunes.