Q: iPod touch wont update iOS 4.3

The wifi update comes with iOS 5

What error message are you getting when you update via iTunes?

iTunes: Specific update-and-restore error messages and advanced troubleshooting

Update Server

Try:

- Powering off and then back on your router.

- iTunes for Windows: iTunes cannot contact the iPhone, iPad, or iPod software update server

- Change the DNS to either Google's or Open DNS servers

Public DNS — Google Developers

OpenDNS IP Addresses

- Try on another computer/network

- Wait if it is an Apple problem

You can't, you need iOS 5 for the wifi update as I said in my first reply.

You have to update via iTunes.

You are trying to update via iTunes when you get the error message.

Try on another computer.