Audacity not recognising its own file type

I have Audacity 2.0.6 running on Windows 8.1

Yesterday I saved a project. It’s listed as “Audacity Project File” in the Windows folder.

Audacity is saying it doesn’t recognise the file type.

Audacity is loading older files of the same type OK, just not the one I created yesterday.

This has happened before. When I ran Audacity today it was as though it was the first time ever - which it isn’t. I had splash screens telling me about features etc. and loading extensions.

Any help please?

To open an Audacity “project” (.AUP file and associated _data folder), use “File menu > Open” and select the .aup file.
To import a normal audio file into Audacity, use “File menu > Import audio” and select the audio file.
To open a new project and import an audio file into it, use “File menu > Open” and select the audio file.

Note that a “project” is NOT an audio file - only Audacity understands Audacity projects.
Note that a “project” is NOT a single file - the .AUP file is just a list of instructions for Audacity and the audio data is separate (usually in the “_data” folder.
More information about Audacity projects here:

This problem seems to have stopped happening. Why, I do not know.