VB.Net Removing Rows from DataGridView

Hi Experts
I have a datagridview with two columns and about 250 rows    There are 20 rowsin the second column with the value "No Information"
and I want to delete these.  I have rigged a button just for testing.

This code for testing works but only gives me a MessageBox 9 times not 20, I thought it would give me 20

   

  Dim DGV1Row As DataGridViewRow
            Dim CheckValue As String

            For Each DGV1Row In DGV1.Rows
                CheckValue = DGV1Row.Cells(1).Value
                If CheckValue = "No Information" Then
                    MsgBox(CheckValue)
                End If
            Next

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This Code is intermittent, sometimes removing 4 "No Information"  and sometimes 8, not 20

         

  Dim DGV1Row As DataGridViewRow
            Dim CheckValue As String
            For Each DGV1Row In DGV1.Rows
                CheckValue = DGV1Row.Cells(1).Value
                If CheckValue = "No Information" Then
                     DGV1.Rows.Remove(DGV1Row)
                End If
            Next

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The data in the Rows is identical each time I run it and I even tried comparing the values length to see if they were not the same
I've also tried variations of For i  = 0 To DGV1.Rows.Count  With no success.

What am I doing wrong??

Many Thanks