Lost sync button and sync greyed out - Windows 7.

Turned on pc to sync with iPod and noticed the sync button had gone and the sync was greyed out on the drop-down menu from File. I've now updated Windows 7, removed Firewall and downloaded latest iTunes. Have de-authorised and re-authorised. Still no sync button and still greyed out on the options.

I don't want to remove iTunes from the PC, if at all possible, as I have a lot of CDs stored there.

Any ideas?