Several users have reported that they were unable to turn Wi-Fi on or off because the setting is grayed out or dim after they updated to iOS 6.1.3. If you experience thisWi-Fi issue, try the following steps and attempt to enable Wi-Fi after performing each one.
- Make sure that Airplane mode is off (Settings > Airplane Mode)
- Restart your device (iPhone, iPad, iPod touch) by pressing and holding the on/off (sleep/wake) button until the red “slide to power off” slider appears, and then slide the slider. To turn back on, press and hold the on/off button until the Apple logo appears.
- Reset your device by pressing and holding the home button and on/off button together (at least ten seconds) until the Apple logo appears.
- Reset Network Settings, by tapping Settings > General > Reset > Reset Network Settings
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