I have an application i am developing on a psc 4420 that i want to connect to a sql server on my pc. i have the code:

Dim con As SqlClient.SqlConnection = New SqlClient.SqlConnection
Dim cmd As SqlClient.SqlCommand = New SqlClient.SqlCommand
Dim da As New SqlClient.SqlDataAdapter(cmd)
Dim ds As New DataSet
Dim dr As DataRow

con.ConnectionString = "Persist Security Info=False;Integrated Security=false;database=SMSM2MDATA;server=192.168.123.50;User ID=sa;Password="

con.Open()

Try
cmd.CommandText = "Select distinct fdept from employee"
cmd.CommandType = CommandType.Text
cmd.Connection = con

da.Fill(ds, "DeptList")
For Each dr In ds.Tables("DeptList").Rows
ComboBox1.Items.Add(dr("fdept").ToString)
Next
ComboBox1.SelectedIndex = 0
Catch exp As Exception
MessageBox.Show(exp.Message)

Finally
If con.State <> ConnectionState.Closed Then
con.Close()
End If
End Try

when testing the code in the debugger on the device, i get a "An unhandled exception of type 'System.MissingMethodException' occurred in System.Data.SqlClient.dll"

i have no idea what is causeing this error. i can run the same code from a desktop app and i get no errors.

any help would be much appreciated.
thanks
dougg