Kerbugg

Downgraded the VB from 4.1.8 to 4.0.16 and it seems much better now...-at least the netduino is getting attached to the guest system...

I'm running 4.1.8 VB on Fedora 16 Linux using Netduino Plus and had the same experience, but was able to get it going by doing the following:

assuming you can see the Netduino Plus in Linux: using command lsusb or equivalent for your Linux version,

then boot VB (with guest additions and extensions). Once in VB confirm that the Netduino shows up under device menu drop down in VB. If so yon can launch C# IDE and the first time it will typically send code to the Netduino after a 2 -4 second delay, but will stop with the waiting on ... Debug... Restarting msg and sit there forever - if you want to allow the IDE to continue you need to use the device drop down & unselect the Netduino & then immediately select it again via the checkbox. The IDE will then continue as normal.

The method of unselecting then reselecting works every time as long as the Netduino shows up in the VB box drop down while running the guest O/S. You can also try the same after booting VB if necessary just prior to launching the IDE if it doesn't show up then.

BTW, if you get to the ...restarting msg after sending code, you can stop the IDE at this point if you don't care about debugging assuming you also don't need the console output because the code is actually already transfered go the Netduino. Just hit the Netduino reset button and your new code will begin execution.