Q: ipod nano 4th generation cannot connect with iTunes.

What happens when you try to connect it to iTunes?

If possible, try a different USB docking cable, to rule out faulty cable as the cause.

When you connect it, watch the iPod's screen.  Does it say "Do not disconnect" or "Connected" or give other indication of a connection?  Or does it only show the battery charging symbol?  Or does it not react at all to being connected?

Is your computer running iTunes a Mac or Windows PC?  If Windows, what version?

I have uninstalled all apple software mentioned and reinstalled iTunes. Still it will sync for a second but nothing transfers.

I have added 3 CD to my iTunes but they don't transfer to my iPod. It just quit sync after new version of iTunes.

iPod nano, Windows 7, current iTunes 12

Yes it does show up in iTunes when connected. When I updated to iTunes 12.3.3 the sync quit working.

I uninstalled iTunes, Apple Update Service, Mobile software, etc and even deleted from Registry. Then I re-installed iTunes, Quicktime, Update service, etc. Still am getting the same results.

Why are you replying in this topic (someone else's topic)?  I posted a reply in your topic, the one you created

Re: Can't sync iPod and PC all of the sudden.

because I thought I was in the wrong thread. I have a ipod nano not a ipod classic.

it only show the battery charging symbol.

If you only see the battery charging symbol, that indicates there is no data connection between the iPod and MacBook.  There is a power connection.

If you have not already, do a Reset (restart) on the iPod.

Learn how to reset your iPod - Apple Support

Disconnect all USB devices from MacBook.  Connect MacBook to its power adapter, so that it's not running on battery power.  Run iTunes and connect iPod to a direct USB port on MacBook, by itself.  If MacBook has multiple USB ports, try them all.

If there is no change (iPod still just shows battery charging symbol when connected), put the iPod into Disk Mode

Putting iPod into Disk Mode - Apple Support

Connect it to MacBook in the same way.  And difference?

If no difference, there are three key possibilities:

- Problem with USB port.  Try something else on MacBook's USB port(s), such as a USB flash drive, to confirm port(s) working.

- Problem with USB docking cable.  The cable may be damaged or worn out, and only connecting for power (not data).  If possible, try a different cable to rule out faulty cable.

- Problem with iPod.  For example, iPod's dock connector may be damaged or worn out, and only connecting for power; visually inspect dock connector for debris blocking connection points.