Internal Error while Processing Mixdown

Howdy,
 
I'm getting the error below whenever I try to perform a bounce to tracks or an export on this one particular project.  Other projects render down with no problems.  Using SONAR Platinum with the Lexington update.  Anybody have any suggestions as to what to look for that might alleviate the issue?
 
I have already tried SONAR restart and a reboot of the PC to no avail.
 
 
 
"An Internal error occured while processing the mixdown. The operation was unsuccessful
Catastrophic failure"