Missing Audio Data Block Files

A friend of mine is working on a file we recorded together, on Audacity 2.4.2, and he received this error:
WhatsApp Image 2021-05-02 at 13.15.41.jpeg
He doesn’t know why. He says he edited the file for a while, and when he tried to re-open it later he got this.
He sent it to me using Wetransfer and I’ve tried to open it on my computer, on Audacity 3.0.2 and got this error:
Then I get a file consisting on 1 hour of silence.

I’ve asked my friend to look for e080021b.au anywhere on his computer, but he found nothing.
We both have Windows 10.
The funny thing is that in the _data folders there’s a total of 893 files, 720 MB, so it seems like everything is there… Audacity just doesn’t know it.
My friend tried using the software Recover My Files, but it found no .au files. He tried looking in C:\Users<your username>\AppData\Local\Audacity\SessionData, but it was empty.

Does anyone have any idea how the project can be recovered??
I’m attaching the log file (in 2 parts, too big), and all the projects file are available here:

Thank you all…
logB.txt (779 KB)
logA.txt (996 KB)

Audacity 3.0.2 will successfully open shows from the earlier Project format. That’s not the problem. Being missing one of the AU files means you’re going to have a 6-second hole in the show. That’s not the problem. Chances are really good that the AUP project manager file is damaged and that means you have no show. Sometimes, when the moon is right, you can recover a raw, unprocessed recording without the AUP file. You can never recover an edit that way.

Open the AUP file from the show in a text editor. Do Not save anything. It should look something like this.

This one has been cleaned up for its picture. Yours won’t be neat and orderly like this. If it’s blank, has nonsense graphic characters or lots of NUL NUL NUL. that’s the end of the world.

Was the show part of a machine backup? Do you have all of the work as separate WAV files so you can start over?

Do either of you have any backups?

Audacity 3.0.2 doesn’t save Projects this way any more and it has improved backup processes.


I’ve opened the AUP file in a text editor and it looks fine, no NUL or weird characters. I’ve saved it as a separate txt file and I’m attaching it here. Is there something I can do with it to fix the project?

There’s no backup of the computer or audio files, and it was recorded directly to Audacity so I don’t believe there are separate WAV files (please correct me if I’m wrong). There’s also no Antivirus etc. that could have “swallowed” the files.

Anything I can do from here?

AUP file in the text editor.txt (182 KB)

Don’t get all excited, but that’s not as terrible as it could be.

See this line from your file?

Screen Shot 2021-05-06 at 9.35.38 AM.png
It’s buried in your text file about three lines down.

Your show should be labeled Learn with Ido and Dana.

Learn with Ido and Dana.aup
Learn with Ido and Dana_data

Both the AUP file and the _DATA folder have to be labeled exactly that. The AUP file and the _DATA folder must be in the same location or folder and the location must be a local drive, not a network or cloud drive.

Post back.


Yes, that’s indeed the situation:
What do I do now?

What do I do now?

Prepare to recut the show. Or maybe reshoot and recut the show if you have no backups anywhere.

I think that’s a confused or broken Project Manager file. In my simple example, the upper blob of programming says “Channel 0” and the lower blob says “Channel 1”. You can extrapolate that into first channel and second channel, in English, Left and Right, since I got that from a stereo show.

Your AUP file also neatly divides up into two sections, but they’re both labeled “Channel 2.” I think that’s impossible—someone may post and correct me. I think there was an event during the edit that confused Audacity into producing a bad manager file. I’m not a developer or a programmer, so that’s as far as I go.

The developers have their own web presence, so the only hope is a senior forum elf drops in and knows what to do.

Meanwhile, if you don’t have backups, start planning a reshoot. I Export each raw performance as a separate, perfect-quality WAV file so if everything hits the fan, I can recut the show from the WAV files and not have to shoot anything again. I still have backup WAV files from shows years old. Producers have a habit of calling and wanting archive work.

“Hey, Koz, remember that voice track you shot in the warehouse?”


Open the _DATA folder. You should have a pile of little .AU files under several folders depending on how complex the show is.

Each one of them should open and play in Audacity. They’re tiny (6-second) sound files. Do they?


Yes! I have the tiny .au files. They open in audacity, and in most of them I hear what I’m supposed to hear :slight_smile: (some have silence). Can I rebuild the show from them?

The AU files have intentionally scrambled filenames. If you have an edit in progress, you can’t use the file time and date stamps to help you. The AU files are about six seconds long and if it’s a stereo show, they alternate Left and Right sound.

How long is the show? You see where I’m going with this? It’s not impossible to reconstruct the show, but it’s not likely. You have to organize the AUs by place in the shooting script—by hand—and then unscramble them by sentence and content.

What was the show? Interview with the governor? If it’s a respected university teacher, it’s not unusual for them to make a point and then reiterate the point later in summary. So there’s two AUs with the same words.

Also, as if that wasn’t enough. some Projects may use fractional AUs.


Since you have the AUP file, you can open that and try the order of the AU files listed there.

Screen Shot 2021-05-07 at 2.29.56 AM.png

Ok so I’ve tried that, but I see that some of the au files listed there don’t exist…

some of the au files listed there don’t exist…

That brings you back to constructing the show by hand, matching up words and sentences with no guarantee of success.


Damn. Well, thank you anyway.