HELP! Corrupt .aup file - 17750 orphaned files.

Hi Everyone,

I’m in a bit of a pickle, having worked at a festival recording the output of one of the stages last friday, someone put my macbook (running 10.8.3) to sleep once the show had stopped.
Having then tried to save the project, it appeared to save correctly, however on reopening - showed that I had orphaned files - and not a small number of them at that.

Now here’s the question. I know I have all 9 -10 hours of recorded data in the project folder file, and I am aware that I am not the first person to experience a problem like this.
How am I going to go about putting this massive jigsaw back together again?

I am mindful that the general advice is to rename folders and files in numerical order and import them back into audacity, but there doesn’t seem to be an agreed route for this.

I have tried the audacity recovery utility, but that just errors when I set it to run.

The project settings are 48000hz 24bit Stereo. the individual .au files are also at 48000hz but when i import them they’re mono.

Thanking you in advance for your patience and help in this matter.

They are mono yes. In the older Audacity, they would alternate Left - Right - Left - Right. Koz

Did they close the laptop? I’ve done that and my recording seemed to survive the experience, but I wasn’t running 10.8. I was horrified what I had done, but it seemed to pickup and run from where it was.

That would not work if it was recording, playing or paused when they did it.


Quite what happened is something of a mystery, the result however remains the same.

14.8Gb of folders with ~512 800kb files in each folder

Somehow I have to get that little lot into 1 stereo recording.

Any ideas?

What happens when the project opens - is the entire audio silenced and orphaned?

Are you sure you only recorded nine or 10 hours? Audacity cannot store more than 2^31 samples as a project, as noted in the Release Notes .

At 48000 Hz this implies a maximum storage of just over 12 hours 20 minutes. 17750 .AU files divided by 22 .AU files per minute is about 807 minutes or nearly 13.5 hours.

The instructions are at as you point out. Yes the files must be sorted into time order then renamed into a consistent alphanumerical sequence. You can do that with Automator.

Make sure you get the 1.2 recovery utility for Intel Macs and don’t feed it more than 1000 AU files at a time. Stereo recovery will probably not be perfectly channel-correct because AU files for each channel will be written at almost the same time.

You may also be able to use the terminal and the Linux recovery procedure as mentioned on the Crash Recovery page. In that case, follow the instructions to use the Append Import plug-in to import the renamed files, and not the 1.2 Recovery Utility. Append Import is limited in the number of files it can import at a time, according to how much RAM you have.


Maybe it’s not the Sleep Cycle that did it. Audacity has a very firm limit on the amount of data you can smash into a Project. Audacity is not a surveillance recorder; it’s not open ended. Gale or Steve will drop by with numbers, but as the quality of the work goes up, the number of hours goes down, and you picked a very high quality format.

You’ll notice I’m not racing to your rescue here. There may be no rescue. You may have no show.

rename folders and files in numerical order

That stopped working a long time ago. The filenames are now scrambled for some reason I don’t know. The latest technique is to arrange them in time and date order. I thought there was a published process for this. I can look.

I know under certain circumstances we actually recommend some of the older rescue tools for a particularly difficult job. You are running Audacity 2.0.3, right?


OK Thanks for getting back to me Gale, I appreciate you’re probably busy and am grateful that you’re taking your time to look at this.

When I open the .aup file, it takes it’s time opening, i even get the spinning rainbow of doom (which in this instance just tells me that audacity is working very hard)
when it eventually opens, the left and right channels are blank then, after some more spinning rainbow action, it comes up telling me that : this project has 17750 orphaned block files.

asks me very politely if i would like to ignore them, close the project without saving, or delete all the block files.

At this point I have always elected to either ignore the files (which does nothing) or close the project without saving.

I have tried importing the individual .au files from one folder into audacity, and am likling the idea of renaming them in date and time order.
Your advice about the limits of audacity intrigues me. and certainly this entire episode is going into the “lessons learned” box of my life.

Hi Kozikowski,

Basically I am mindful that the entirety of Friday’s recording of 9 amazing artists unique festival performances, may indeed be lost to the four winds. But I cannot and will not go back to my master empty handed saying “well i looked at it but couldn’t work out what needed to be done, so you lose out - sorry” I would get a slap for that and rightly so.

I know that i have a jigsaw on my hands, I have a lot of .au files and somehow I have to join the dots to get the .au files to look like one glorious beautiful (albeit slightly wonky if necessary) .aup file.

I am running 2.0.3 and have tried to find the audacity repair utility verson 1.2, but the audacity page links to version 1.1 and google is of little or no help.

OK I have a plan, but need to know one detail.

It seems to me that audacity saves left and right channel information separately.

That being the case, is there a format for this saving, is each file alternately left and right channel?

So far, I have copied the contents of each folder within e00 to a single folder and ordered the files in date and time order.

I now have files that cover the entire recorded period. I just need to paste them into a left and right channel recording within audacity, for the entire recording, and in a week or so I should have a complete project for the entire night.

The problem I have now is there is no way for me to identify easily which is left and which is right channel - being as it is that audacity just sees each individual file as mono.

Am I battering my head against a brick wall here or am I missing a step?

Ok, i’m sorry for my previous, I have since abandoned plan A in favour of plan A2, which uses a combination of file management and the recovery utility.

I have made significant progress and will let you know how I get on

Thanks once again


There is no obvious way to tell which channel is which, given the “random numbering” scheme of AU files.

However from tests I have done getting file creation times in milliseconds from Windows PowerShell, Audacity still does write the left channel before the right. In that case Windows running the NTFS file system (which has timestamp granularity of 100 nanoseconds or 0.0001 milliseconds) and the Linux ext4 file system (which has timestamp granularity of 1 nanosecond) would in theory be able to distinguish timestamps of left and right channels if the tool you use lets you access that information. But Mac (HFS+) and Linux ext2/ext3 can’t timestamp files to finer than one second.

You do appear to have recorded longer than Audacity supports as a project. What you could have done is exported the recording split up into lengths appropriate to the file format - see . And if you needed a project, copy and paste no more than the limited amount to a new, empty project window so you have two projects.