SONAR was stopped by an unknown process during mixdown (that hasn't happened to me before) but couldn't recover the audio file. After a reboot a wav file shows in the folder (15 minutes short of complete) but I am unable to access it using SONAR or Sound Forge. I need to get the file to the Director, so any help is appreciated.
Audacity can open it as a raw file but does anyone know the Start offset, whether it's Big Endian, (pretty sure it's Signed 24 bit PCM, but when I import as that, Big-Endian, 2 channels, 0 Start offset, and the 48k sample rate it's hissy. )

Can't you start the mix again?  I am imagining/hoping/expecting you would have saved the project's final edits prior to starting the mix down.
 
How far do you have to go back to get to a working version of the project?  Even if the whole project is corrupted, don't you have a backup copy?
 
Bob Bone

If it crashed during the mixdown, you have to have saved it before exporting. Right?  Even if you did not save it right before you exported, you should have at least saved it somewhere. i cannot imagine you never saved the mix when you where mixing it.  I press the save button after every adjustment I make as i have it keybinded to the letter 'S'
 
The exported file will not work. so you need to Open SONAR and re-export it. That si all you need to do. do not play with the exported file, as it was not exported fully!!  Hopefully you save it and/or backed it up before exporting. Make sure you do not have any plugins that require real time bounce and maybe you need to raise your buffers
 
CJ

Yeah, sorry guys: I posted after working 36 hours straight on a project and wasn't clear. At all. hopefully this muddies the water less:
The project file is fine (and yes I have copious backups of previous versions) and save constantly.
The actual question was: is it possible to recover the corrupt stereo mix down of the project that I can see in the folder (1.4GB of data, says it's a.wav file but cannot be opened by anything except as a raw file in Audacity. But when it's opened, it's unusable). The project itself is one hour and 32 minutes and I got within fifteen minutes of the end when the error occurred, so I didn't want to have to re-bounce the entirety of the project if I could recover the portion that was finished, bounce only the last fifteen minutes, and merge the two sections. Unfortunately, I ended up re-bouncing the entire project. This time in thirds (just in case it happened again...it didn't) and then merging those.
I am doing a real time bounce on this project, as some of the soft synths sometimes drop notes and occasionally I hear an effect sound incorrect after Fast Bouncing.
So my inelegant solution was to re-bounce the project in portions in case something bad happened. By overlapping on each portion, I also kept tails and FX from a previous section or going into the next: i.e. instead of breaking up the project into 30 minute segments, I bouncinged 32 inutes of the first section, 34 of the next (2 minutes prior and after what I needed), and 32 of the last section (starting two minutes before the section was interested began)

No ,you will have to RE-export the project. If it crashed after 15 minutes and the mix is 32 minutes, you will not have the full mix anyway. The exported wave file is corrupt and there is nothing you can do about it, except Re-Export the mix as you already did
 

I am doing a real time bounce on this project, as some of the soft synths sometimes drop notes and occasionally I hear an effect sound incorrect after Fast Bouncing.

Just bounce the synths before exporting and you will not have that problem
 
CJ