
Fix 1: Reset Network Settings
Go to "Settings" > "General" > "Reset" > "Reset Network Settings", and then your iDevice will restart.


Fix 2: Reset Restrictions
Go to "Settings" > "General" > "Restrictions", enable restrictions for five seconds and then disable restrictions.

Fix 3: Reset Wi-Fi
Go to "Settings" > "Wi-Fi", enter your current Wi-Fi and choose "Forget this Network", thus your Wi-Fi will be reset. Restart your device now and connect to Wi-Fi again.


Fix 4: Check Date and Time
Go to "Settings" > "General" > "Date and Time", slide to turn off "Set Automatically". Check the time and date on your device, then turn on "Set Automatically" if they are correct.

Fix 5: Reinstall iBooks
Uninstall iBooks on your device and then reinstall it.
Fix 6: Reset Date and Time
Go to "Settings" > "General" > "Date and Time" > "Set Automatically" > "Off". Set the date one year ahead. Go to iTunes Stores now. If you get the error message again, go back to turn on "Set Automatically". Try it for several times, and then the problem will be solved. (This way mainly works for those who update their devices to iOS 6 and can't turn to iTunes Store from Passbook App.)

All above is the six fixes to help you get out of the trouble. Now you can check them one by one. Hopefully you can be able to access to iTunes Stores successfully.