InvalidCastException on select XP machines - vb.net

Question

I am having a problem with a tool that I wrote in VB.NET running on certain XP machines. The tool runs fine and as expected on Windows 7 and XP machines that have .NET 4.0.30319.1022.
I've noticed the XP machines that I am having trouble on are those that did not have .NET 4 even on it, so I went and installed .NET 4 which puts on version .NET 4.0.30319.1.
Here is the error:
Here is the code at line 86 (86 is the For Each):
'_BIOSVer
Dim bios_query As String = "SELECT * FROM " & "Win32_BIOS"
Dim bios_searcher As New ManagementObjectSearcher(bios_query)
For Each info As ManagementObject In bios_searcher.Get()
_BIOSVer = info.Properties("BIOSVersion").Value.ToString()
Next info
I am running Windows Updates for .NET 4 Framework to see if that will fix the issue, but I was wondering if you guys might have a sense of what is happening, or if my code is just wrong.
Updates just finished, restarted. It is running off of .NET 4.0.30319.1022 but still throws that error. Must be my code then.

Answer 1

There are several problems, but mainly BIOSVersion is a string array. Rather than poking into that, you can just get the Name which returns the version info (so does Caption and Description). Since you are after one thing, you dont need a loop, but I left it in as a template:
Dim myver As String = ""
Using searcher As New ManagementObjectSearcher("Select Name From Win32_Bios")
For Each mo As ManagementObject In searcher .Get
' EXAMPLE
'DebugProperties(mo)
' no real need to Loop - just for illustration
For Each pd As System.Management.PropertyData In mo.Properties
' if you do SELECT * and want to find something,
' compare Pd.Name to the target property
' some things can be nothing. Such as when a property does not
' exist on older systems, so always test:
If pd.Value IsNot Nothing Then
myver = pd.Value.ToString
Exit For
End If
Next
Next
End Using
Return myver
This is a helpful WMI debug tool to display all the property names and values (the code above has the call to this commented out):
Private Shared Sub DebugProperties(mo As Management.ManagementObject)
For Each pd As PropertyData In mo.Properties
If pd.Value IsNot Nothing Then
Console.WriteLine("{0} {1}", pd.Name,
If(pd.Value IsNot Nothing,
pd.Value.ToString,
"Nothing"))
End If
Next
End Sub

Answer 2

BIOS Version returns a string array (for more information check this link).
Try reading the data like this
Private Sub Button1_Click(sender As Object, e As EventArgs) Handles Button1.Click
Dim BIOSSearcher As New ManagementObjectSearcher("SELECT BIOSVersion FROM Win32_BIOS")
Dim BIOSVersionInfo() As String = BIOSSearcher.Get(0).Properties("BIOSVersion").Value
Dim BIOSVersion As String = ""
If Not BIOSVersionInfo Is Nothing Then
BIOSVersion = String.Join(vbCrLf, BIOSVersionInfo)
End If
MsgBox(BIOSVersion)
End Sub