Will it break anything in Orion, if we upgrade from .net 2.0 to 4.0?
cblack,
Orion NPM 10.0 SP1 is not fully compatible with .NET 4.0. For more information, see this SolarWinds Knowledge Base article (http://knowledgebase.solarwinds.com/kb/questions/1626/) and this thwack thread.
You need to upgrade all so that it will be compatible each other.