From a Data Table:
All the work is done in one line
'create a SaveFileDialog, to get the file name and path
Dim saveFileDialog1 As New SaveFileDialog
saveFileDialog1.Filter = "Excel files (*.xlsx)|*.xlsx|All files (*.*)|*.*"
saveFileDialog1.FileName = "SuggestedFileName"
If saveFileDialog1.ShowDialog() = DialogResult.OK Then
Dim strFileName As String = saveFileDialog1.FileName
Dim generator As New ExcelReportsGenerator()
generator.GenerateFromDataTable(GetDataTable(), "TabName", strFileName)
End If