Audacity no disk space error has cut my original wav in half

Hello, I just recorded a 1 hour mix, and imported the .wav into audacity to tweak. Upon importing i got an error (which i do not quite remember) followed by an audacity out of disk space error. (I did choose the ‘safe option’ which was presented prior to the import)
I cleared space on my C drive and re-imported the wav only to find that half of it was missing. This is very frustrating as I only have the original .wav which is now half the size and length.

Is there anyway I can recover my full .wav? Thanks to anyone who can help

Im using the installer version of Audacity 2.0.5

What version of Windows are you using?

Assuming you did not export over the original WAV there is no reason it would have changed size. All Audacity should have tried to do is copy data from it into the temporary directory listed at Edit > Preferences: Directories.

You can verify the size of the WAV by looking at it in Windows Explorer.


Note that WAV files are limited to 2GB (or 4GB depending on which spec you read). 1 Hour would be no problem for a “CD quality” file (44.1kHz, 16-bit, stereo), but if you have high resolution audio or more than 2-channel stereo, etc., you could be running into the limit.

Your problem:
DVDdoug is correct! On an older project I ran into exactly the same problem you described. My WAV file appeared to have all of the audio data (judging by it’s size), however when opening the file in either Audacity or any other player/editor it cut out at 32min 21sec. My WAV file had six channels so it ran out quickly. (check this link for WAV file format limitations…

From now on record to an audio file format without this limitation, at least for large projects. I use and recommend FLAC. (

As for “recovering” the audio data…

  • If the WAV file size is greater than 4GB then the audio data is there, but you’ll need a utility that can bypass the WAV container’s 4GB limit and I don’t know of one off hand that can do this easily. If you know, or know someone who knows, how to use Linux then the dd utility can probably take care of splitting the single WAV file into smaller (<4GB) WAV files. From that point you should be able to patch-work your project back together in Audacity and then save it out to FLAC or whatever non-WAV format you want. Of course, the only other way is to re-record to a non-WAV file. Sorry.

  • If the WAV file is 4GB or less then the audio data never got recorded and you’ll need to start over. Again, sorry

Unfortunately, a lot of Flac encoders on Windows are limited to 2 GB size (roughly the same length as a 4 GB WAV file).
Linux does not have this limitation.

A simple workaround for very large projects that keeps the audio in uncompressed audio quality is to export the project in sections.
However, I note that QuantumForce said that the recording was only an hour long. 1 hour at 16 bit, 44100 or 48000 Hz sample rate, mono or stereo, will be well under the file size limit for either WAV or Flac.

I’ve seen that problem before too! In my experience the limitation was due to either…

  1. the encoding program first converted the incoming audio to a temporary WAV file, hence getting stuck at the 4GB file size limitation of the WAV file format …or
  2. the encoding program was writing a “raw data” file out to a FAT32 partition, hence getting stuck at the 4GB file size limitation of the FAT32 file system (File Allocation Table - Wikipedia)

I’ve found that case a is almost non-existent nowadays, but case b still happens from time to time and it’s usually related to a new external hard drive or thumb drive which came formatted FAT32 by default.

The specific problem with Flac encoding is due to the encoder being built with MSVC without 64 bit extensions.

QuantumForce said

I only have the original .wav which is now half the size and length

so (s)he appears to be distinguishing size and length as different things and/or exported the file, which would cause truncation and an error message if there was still not enough disk space. If you copy in the file on import, you need the disk space to do that as well as the space for the export.

Current Audacity should be able to import WAV files between 2 GB and 4 GB without truncation (but not over that size, obviously). Many applications truncate WAV files between 2 GB and 4 GB.

If QuantumForce’s problem is as per your interpretation (the file is over 4 GB), then I think File > Import > Raw Data… would solve it. You just need to remove the click at the start caused by the file headers.

To export to a lossless format that can accept almost unlimited size, try RF64 (though be aware that only “advanced” players such as Foobar2000 will be able to play it).

From 2.0.6 onwards (when released), Audacity on Windows won’t have the 2 GB limitation when writing FLAC because 2.0.6 uses a much more recent libflac that has solved this problem. The problem will still be there with many other Windows FLAC encoders (unless they update their FLAC version).


Interesting. I remember a similar issue with FLAC that was addressed a few years ago. So, after your post, I dug through the flac-dev mail list to look for it and found this message… [flac-dev] 2GB limit? …posted shortly before the latest FLAC version was released. I couldn’t find a more recent post addressing the 2GB/4GB issue, but if you’re reasonably sure that building it on MSVC w/64bit extensions will fix it I’m sure they would appreciate you dropping them a message about it!

You’re correct, Gale. QuantumForce was talking about the source file being altered. In my initial reading I thought QuantumForce was referencing the output file that was created by selecting “safe mode” in Audacity, which, of course, would be truncated because Audacity ran out of disk space during it’s creation. My misunderstanding!

I’m not saying that (just) building with 64 bit extensions will fix the problem, but rather the reverse of that - that 32 bit has an address size of just over 4 billion, so the maximum number of samples that Flac can count using 32 bit is just over 4 billion. Assuming compression of around 50%, that works out at around 2 GB. So when limited to 32 bit numbers (building without support for greater than 32 bit) sample counts much over 4 billion will cause an error. The “off_t” issue mentioned by Erik is one such place where the 32 bit issue applies.

Thanks for explaining further, steve! I really appreciate your, Gale’s, and the others’ efforts in helping with the support and development of Audacity!