Why can't use ManagementObjectSearcher in VS2010 C#

Question

I'm trying to use the code from this post: get com port number of an USB adapter

Then I got this message: why?

Answer 1

You have to add a reference to System.Management Manually through VS 2010.

1. Right Click on Project, Add References

2. Select the Assemblies Tab and Search for System.Management . Then Add Reference.