title: Getting F1 on Datagridview header when Importing from Excel (VB.Net)
body: <p>I have in my project 2 buttons to import from Excel and export to Excel and a datagridview. I can import Excel files with no problem but when I export from datagridview to Excel and try to re-import that file I only get just one column header with "F1" in it:</p>
  
  <p><a href="https://i.stack.imgur.com/zdyfO.jpg" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/zdyfO.jpg" alt="enter image description here"></a></p>
  
  <p>This is the code for export button:</p>
  
  <pre><code>Private Sub Button3_Click(sender As Object, e As EventArgs) Handles Button3.Click
      'Creamos las variables
      Dim exApp As New Excel.Application
      Dim exLibro As Excel.Workbook
      Dim exHoja As Excel.Worksheet
  
      Try
          'Añadimos el Libro al programa, y la hoja al libro
          exLibro = exApp.Workbooks.Add
          exHoja = exLibro.Worksheets.Add()
          ' ¿Cuantas columnas y cuantas filas?
          Dim NCol As Integer = DataGridView1.ColumnCount
          Dim NRow As Integer = DataGridView1.RowCount
          'Aqui recorremos todas las filas, y por cada fila todas las columnas
  
          'y vamos escribiendo.
          For i As Integer = 1 To NCol
              exHoja.Cells.Item(1, i) = DataGridView1.Columns(i - 1).Name.ToString
          Next
          For Fila As Integer = 0 To NRow - 1
              For Col As Integer = 0 To NCol - 1
                  exHoja.Cells.Item(Fila + 2, Col + 1) = DataGridView1.Item(Col, Fila).Value
              Next
          Next
          'Titulo en negrita, Alineado al centro y que el tamaño de la columna
          'se ajuste al texto
          exHoja.Rows.Item(1).Font.Bold = 1
          exHoja.Rows.Item(1).HorizontalAlignment = 3
          exHoja.Columns.AutoFit()
  
          'Aplicación visible
          exApp.Application.Visible = True
          exHoja = Nothing
          exLibro = Nothing
          exApp = Nothing
      Catch ex As Exception
          MsgBox(ex.ToString)
      End Try
  End Sub
  </code></pre>
  
  <p>What can I do to solve it??</p>
  
  <p>Thanks.</p>