Word 2007 suddenly stops recognising endnote

Switched to office 2007 few months ago. All well until 2 days ago when endnote stopped functioning - wouldn’t look up references and then later when programme restarted that it “could not initialise database support”. The noticed Word document had lost the “Add-In” tab that allowed you to get to endnote from Word, and endnote itself was unable to initiate any “Cite while you write” options. Have uninstalled and reinstalled both endnote and the office 2007 suite but still Word doesn’t recognise endnote and vice versa. It was working fine before. Please can anyone help?