HELP! "Fatal execution engine error"

HELP! "Fatal execution engine error"

i just hope anyone could help me with this. im running ccnet with nant, nunit and ncover integrated to it, with a 1.1 Framework.  i'm getting this error message whenever i build ccnet, though the build show Success:

C:\Data\Projects\CInteg\Build Automation\EquityServices\Release 22\Scripts\NAnt\main.xml(834,4):
External Program Failed: C:\Data\Projects\CInteg\NCover1.3.3\NCover.Console.exe (return code was -2146233082)

Fatal execution engine error.

i have a total of 9 assemblies to be tested. but only 6 of them shows this kind of error. i could use a little help on this one.. thanks!