Help?? A Corrupt Audio Region Was Detected And Padded With Silence when opening .cwb

I have a client that has been recording off and on for quite some time.
I have saved his files as .CWB to an External Drive. I planned to open
and work on at a later date.

When attempting to open the files, It gives an error message that says.
A Corrupt Audio Region Was Detected And Padded With Silence
Seems all the drums come up as silence, some guitars? It varies.

Recorded with Sonar 8 Producer but I had opened and saved the project(.cwp) files in Sonar Producer 8.3(I believe).
To be clear, I had saved the .CWB with the same version of Sonar I am using now. So I'm not using a different version
of Sonar per say.

The message makes me think I'm going to have the big one!


Is there any way to open these files or recover the files within the .CWB
BTW, The .cwp files are long gone.

Am I doing something wrong? Sampling or bit in Sonar? Do I have to check a little box somewhere?
Have I lost everything? I'm hoping there is an easy solution and I'm just overlooking something.
Help

.cwb is a good format for co-operation over the net or moving projects otherwise, but it should never be your only saving format.

First of it's unlikely that all of your backups are corrupted.  Do you have more than one? 
For clients I have 3 plus the original one stored locally if they are a work in progress. I'm afraid one copy of a project is not really a safe way of storing data. But if so there still might be something that works. 
 
My question is why do some  Bun / CWB files go bad in the first place? 
I understand the CWP file system and it seems straight forward. 
The CWP file contains the project MIDI and configuration data, the audio folder contains the wave files. A wise user will always use "Per Project" audio folders to keep things in one place. 
 
I just tried this, new project, 2 midi tracks, 1 audio   and I saved as a CWP first and checked the "copy all audio with project" box. The audio is in the folder. 
 
I then saved as a CWB file to a new location and all that is there is the CWB icon, the option to copy all audio is grayed out when saving as a bundle. 
 
So this is scary to me,, this means the audio must now be hidden from all but Sonar!!. With a CWP file audio folder, any software can still retrieve and use the audio. It is not encrypted.  
I noticed both files where the same size to the Kb. 49.3, so bundle files do not compress the audio, they just hid it. So this leads me to beleieve the audio is still in there and possibly in original condition. 
 
So it's a Sonar bug that either encrypted it badly, or the new version sucks at reading the file. 
 
Possible issues- You are using a different sample rate? 
Plug in's and version are changed from 32 to 64 bit ?
 
I would try and re create the system you saved the files on. 
 

We backed up to 3 different drives.
I liked the per project folders. However, when they first started the per project folder,  I remember reading it was to keep your audio per project in 1 folder so as Sonar would not have a huge folder of audio to riffle through combined with many projects. I had no idea that bunfiles/.CWB had gone bonkers since Sonar 4?

We thought we were being safe with the client taking backups after each session, I backed up to another external and I copied from that external to my home computer. Well, surprise, surprise.

So I am researching sending my hard drive with the deleted project files to a data recovery business. However,  most don't recognize .cwp and .cwb as legitimate extensions used by windows. And they would have to be able to return the folders, including all the data, with timestamped audio, back to the original location.

The band is from different parts of the USA and the singer lives in Canada, so the horrific thought of re-tracking everything isn't even a possibility.

As a paid registered user with SONAR, still not a peep from anyone at SONAR TECH.

The Per Project Folders I still have for other artists and my own, I will backup by copying the entire folder, I will also save as OMF as this may be my final straw with ever using SONAR.
My client from this 14 song botched backup by SONAR, also a paid registered Sonar user said he will be using something other than SONAR from now on. And the threads on my Facebook Page have also caused many to be alarmed.

I do appreciate the advice on the issue, truly.

Again, I did not know that .Bun and Bundles were NOT stable since Sonar 4
I had been saving/backing up files "Save AS Cakewalk Bundle". The Project folders
are long gone. that is the drive I may send to recovery company. I have used 3 different
recovery software and it will not find the project folders with the data. It does find 5000 plus
.wav files which would be impossible to go through and line up with other tracks.

Chain of events.
I would backup Bundle to my C drive.
I would back up Bundle to one of my external drives
I would backup Bundle to clients drive.
All project folders and data deleted from C Drive as we thought 3 copies of the Bundles
would be plenty safe backup.
 
As a PAID REGISTERED Sonar customer, I still have not heard a peep back from Sonar Tech.
Great customer service eh?