Problem saving a project in Audacity


I have Audacity 2.1.3 and Windows 10.

In May 2016 I learnt and used Audacity to produce an art composition. I really enjoyed this software.
Today, I tried to Save As a .aup project file I’ve done last year and I tried to save a new project in Audacity. I get the same error message for the 2.

Warning: ‘Save Project’ is for an Audacity project not for an audio file.

Please, I need help for this as I am stuck.

Thanks in advance.
Flower Canada

and it then goes on to tell you to use “Export” if you want an audio file that will play in other apps.

It’s a “warning” not an “error”.

Hi Steve,
Thanks for your explanation. I had used Audacity for a whole composition over months and never saw this “warning” message.
Flower Canada