why won't my iPod touch on IOS 9.1 restore through iTunes when every thing is up to date

Try putting your iPod in recovery mode.

What exactly happens when you try to restore via iTunes?

Error message?

Solve network errors

Errors: 17, 1638, 3014, 3194, 3000, 3002, 3004, 3013, 3014, 3015, 3194, 3200. You might also see these alert messages:

• "There was a problem downloading the software."
• "The device isn't eligible for the requested build."

These alerts mean that your computer is either having difficulty contacting the Apple update server or communicating with your device. Check your computer for software or settings that might cause communication issues between your computer and Apple or between your computer and your device.

If you still see the error message, check your security software.

Check your security software

Errors: 2, 4, 6, 9, 1611, 9006.Sometimes security software can stop your device from communicating with either the Apple update server or with your device.

Check your security software and settings to make sure that they aren't blocking a connection to the Apple servers.If you still see the error message, check for USB connection issues.

Check your USB connections

Errors: 13, 14, 1600, 1601, 1602, 1603, 1604, 1611, 1643-1650, 2000, 2001, 2002, 2005, 2006, 2009, 4005, 4013, 4014. You might also see a message that includes "invalid response."If the USB connection between your device and computer is interrupted, you might not be able to update or restore.

To narrow down the issue, try different equipment:

• Use the USB cable that came with your device, or a different Apple USB cable.
• Plug your cable into a different USB port directly on your computer. Don't plug it into your keyboard.
• Try a different computer.
• Solve other issues with the USB connection, then with your security software.