This VS2008 or higher extension uses a LINQ statement to remove duplicate items from a string array but is not case sensitive, also you might like to leave the sort/order-by in the extension or remove it.
Example
Dim Names() As String = {"Bob", "Mary", "bob", "Bob", "Jane", "Kevin", "Jane"}
Names = Names.RemoveDuplicates
For Each Name As String In Names
Console.WriteLine(Name)
Next
Returns
bob
Bob
Jane
Kevin
Mary
Extension (place in code module)
<System.Diagnostics.DebuggerStepThrough()> _
<System.Runtime.CompilerServices.Extension()> _
Public Function RemoveDuplicates(ByVal sender As String()) As String()
Return (From value In sender Select value Distinct Order By value).ToArray
End Function
Microsoft MVP, Uses Microsoft Visual Studio ecosystem building web and desktop solutions