Q: how do i get i tunes to recognise my i pod 4th generation

Hello there, CliveFromBR.

The following Knowledge Base article covers the issue you're having with error 2005:

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

http://support.apple.com/kb/TS3694#error2001

Specifically the following:

Error 2000-2009 (2001, 2002, 2005, 2006, 2009, and so on)

If you experience this issue on a Mac, disconnect third-party devices, hubs, spare cables, displays, reset the SMC, and then try to restore. If you are using a Windows computer, remove all USB devices and spare cables other than your keyboard, mouse, and the device, restart the computer, and try to restore. If that does not resolve the issue, try the USB issue-resolution steps and articles listed for Error 1604 above. If the issue persists, it may be related to conflicting security software. If the errors persist on another computer and known-good USB cable, the device may need service.

Thanks for reaching out to Apple Support Communities.

Cheers,

Pedro D.