Checking value of property of type UnauthorizedAccessException

I'm trying to figure out if a user has admin rights on a particular server by calling the following code:

<!-- language: lang-vb -->

Dim serverContext As New PrincipalContext(ContextType.Machine, myServerName)

If they don't, the ConnectedServer property on the PrincipleContext object turns into type System.UnathorizedAccessException and the value is {"Access is denied."}

But I can't seem to run any check in code to see if this is the case or not or wether the connected server property set normally as a string.

These won't work, and I can't figure out why

<!-- language: lang-vb -->

Dim bln1 = serverContext.ConnectedServer = "Access is denied."
Dim bln2 = TypeOf serverContext.ConnectedServer Is System.UnauthorizedAccessException