Thanks Moors. Got it. Worked fine.
Feedback to other newbies. When using Windows Notepad to save a file you dont want “.TXT” on the end of the file.
I saved from Notepad as {blinky.ino} but I didnt realise Windows had thoughtfully saved it as {blinky.ino.txt}, so that the CLI compiler didnt recognise/find the file.
Save in Notepad with quote marks " around the file name (eg “Blinky.ino”) and Notepad doesnt save with the .TXT extension.
Maybe I am the only person who didnt know that- but thought I’d share just the same…