Process completed with exit code 128

[teognost]

One of the builds failed at some steps of type "Run program" with a message like this:

6/27/2012 3:16:13 PM: Building project step 'add solution result'...
C:\Program Files\VisBuildPro8\Tools\msxsl.exe "C:\Reports\BuildsOutput\2012.0627.11.0\results.xm l" "C:\BuildsIntraday\ffng\Install\VBP\Processing\Add SolutionResult.xslt" -o "C:\Reports\BuildsOutput\2012.0627.11.0\addedResul ts.xml" "buildLabel"="2012.0627.11.0" "solutionName"="ExcGat\OrdGatClientHelper.sln" "status"="Success" "duration"="10" "output"="\\DEV-BLD02\Reports\BuildsOutput\2012.0627.11.0\ExcGat_O rdGatClientHelper.sln.txt"

Process completed with exit code 128

6/27/2012 3:16:14 PM: Building failure step 'Send Gen Mail- failure of failure step'...
cscript.exe "C:\Program Files\VisBuildPro8\Tools\SendMail.vbs"
Process completed with exit code 128'

Any idea what could cause this problem?
Previous build went ok.