"Downgrading iOS 9 to 6 on my iPhone 4S for WiFi fix: I don't see why Apple will not provide signed iOS's for phones which are long past shelf life, like my iPhone 4S. I am facing issues with WiFi connectivity on my old phone and I read on another blog that the error may be rectified by restoring the phone from iOS 9 to 6."
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Downgrading the iOS to Fix iPhone WiFi:
You Can't. Downgrading the iOS is not an option. It is the way Apple designed the iPhone iOS. Being so olde of a device, it is prone to bugs ans failure. Apple typically provides update for 7 years of a device or operating system release, and then discontinues them (unless a pandemic were to occur). So, take this as a goo reson to upgrade to a much newer model.
Troubleshooting iPhone WiFi:
A few thoughts to try:
I. Start Here: If your iPhone, iPad, or iPod Touch won't Connect to a Wi-Fi Network - Apple Support
II. Clear the Temporary Internet Files:
III. Restart your Router:
- Power: off the router
- Wait: 30 seconds
- Power: It back on
IV. Reconnect to your Network:
- Go to: Settings
- Tap: Wi-Fi
- Disable: Wi-Fi
- Wait: 30 seconds
- Enable: Wi-Fi
V. Add Back the Network:
- Go to: Settings
- Tap: Wi-Fi
- Remove: the network
- Wait: 30 seconds
- Add: the network back