A problem I've run into a couple of times now which I've not been able to resolve and starting to wonder if it's my machine.

in several tutorial's and/or sample code, when I run the code it stops on a DrawPrimitives call stating a "Method Call was invalid error"

Happens in QuadTree XNA-GS DrawableGameComponent - http://www.codeplex.com/quadtreeload - when it tries to draw line primitives (comment out line it's fine drawing alll other primitives)

and Patch Terrain - http://www.codeplex.com/patchterrain - when trying to draw indexed primitives.

Most MS samples seem to work but I'd like to know if it's just me or a simple fix.

Damn strange.