Cannot connect to iTunes Store: THE SOLUTION
Go to Settings > General > Restrictions.
Enable restrictions. Wait 5 seconds. Disable restrictions.
It should now work!
If this doesn't work those are other things you should try.
Alternative #1
Reset your network settings
Go to Settings > General > Reset > Reset Network Settings
and then restart your device.
Alternative #2
Go to Settings > Wifi > {YourWiFiNetwork}
Press on the blue arrow and choose Forget this Network
Restart your device and retry.
Alternative #3
Uninstall and then reinstall iBooks.
Alternative #4
Make sure date and time are correct.
Go to Settings > General > Date & Time.
If the option exists, turn off Set Automatically.
Verify the time zone and time are correct. If not, adjust them.
If everything was correct and the option exists, turn on Set Automatically.
Alternative #5
If your device is jailbroken delete the file /private/var/mobile/Library/Caches/com.apple.mobile.installation.plist
And then restart your device.
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