How on earth do I reply to an existing discussion?

I'm trying to post an additional comment on to an existing discussion but the Reply button is inactive - duh !!!!!

That might mean that the thread is locked either becauses the moderators do not want the discussion to continue or after a period of time this happens automatically.

 

Can you give the name of the thread or better still the URL for the message?

 

If you locate the wording  Message 1 of 1 (1 View)  on the message that first number is a link and so right mouse click on it and select Copy Shortcut and then paste it into a message here,