Dear Sir/Madam:
I wonder if you could help me to recover the connection between the project file and its data folder so I can open the file again. When I finished recording, I closed the file and in order to organize my files I changed the name of two files (changing the names of their respective data folders, but I ended up losing the connection between audio and data files, for the two recordings. 
Is it possible to recover them? I hadn´t exported them yet, since I still had to clean them. Many thanks. Sandra: an upset teacher. 
If you open the AUP file in a text editor (notepad?) and read it (don’t save anything), it will tell you what the original show or Project name was. In this illustration, my show (projname) was called piano2split.
It’s not easy to resolve naming problems outside of Audacity because the names are hard-burned into the programming. The best way is rename everything back where it was and then try to open the show. The AUP file and the _DATA folder can be anywhere, but they have to be close to each other. Same folder or directory. Try putting both on your desktop.
Koz
Dear Koz, many thanks for your reply. I did managed to open de aup file in notebook, but because I had opened and closed the file several times, I don´t know if it saved itself with a different name, because the name between the inverted commas was different from the name I gave it originally and I actually replaced it with the original name but the system still couldn´t find it. I guess I´ll have to record it again and take this as a learning experience.
Many thanks for your valuable help.
Kind regards.
Sandra.
I guess I´ll have to record it again
Not yet.
The name burned inside the AUP file is generally only changed inside Audacity. So it doesn’t matter how many times you opened and saved under a different name, the show or project still only has one name.
projname=“piano2split_data”
The project name, when I recorded it originally, was piano2split.
I think I left out a piece of the explanation. The AUP file and the _DATA folder names have to match. It is required.
I expect to double click the AUP file (in that example) and Audacity should launch itself and open the show.
You haven’t done anything fatal yet. I expect you to correct your file and folder names and the show to open. If you deleted either the _DATA folder or the AUP file, then that can be the end of the world. You generally need both.
Koz
Once you open the project twice with a different _data folder name in the AUP file, Audacity usually silences the data.
Any renaming or copying needs to be done in Audacity with File > Save Project As… .
Gale