Didn't report a specific problem... It just reported that execution was stopped (right after the splash screen went away and before the main window came up). Other than being a desktop Dell... the other machines are either HP laptops and desktops there are no obvious differences. ArcMAP R10 comes up and runs fine on it... At first I suspected it was a license checking problem; but when I run the old R9.3 version on the same Dell machine it doesn't even display the splash screen just tells me that execution stopped and it's checking for a solution. I've considered what might be different, memory, etc. but all appears to be consistent with requirements to run an ArcObject standalone routine?