Good afternoon Andy Swain

It seems that quite a few users are experiencing this - I didn't - and below are some of the suggestions that are reported to have worked (not in all instances).
Try them in the order I have put them, starting from the least drastic.
  • In your Excel settings, find and untick the Ignore Other Applications that use Dynamic Data Exchange (DDE).
  • From the Windows Start menu, choose Run and enter Excel.exe /regserver. This will force Windows to re-register all it's registry keys
  • Try repairing the installation :
    1. Open Control Panel and click on Programs and Features icon.
    2. Now click on Microsoft Office entry present in the list and click on "Change" button.
    3. Now select "Repair" option and click on "Continue" button.

HTH

DominicB