Try the remaining actions of:
- iOS: Not responding or does not turn on
- Also try DFU mode after try recovery mode
How to put iPod touch / iPhone into DFU mode « Karthik's scribblings
- If not successful and you can't fully turn the iOS device fully off, let the battery fully drain. After charging for an least an hour try the above again.
- Try another cable
- Try on another computer
- If still not successful that usually indicates a hardware problem and an appointment at the Genius Bar of an Apple store is in order.
Apple Retail Store - Genius Bar
Also as necessary:
If you don‘t see your connected device in iTunes for Mac
Or
First:
iTunes: Fix iPhone or iPod Not Detected in Windows 10
next try
iPhone, iPad, or iPod not recognized in iTunes for Windows
- I would start with
Removing and Reinstalling iTunes, QuickTime, and other software components for Windows XP
or
Remove and reinstall iTunes and related software components for Windows 7 and later
- New cable and different USB port
Also see:
iPod not recognised by windows iTunes - ASC
Troubleshooting issues with iTunes for Windows updates
- Try on another computer to help determine if computer or iPod problem