You cannot use the Name box to rename a chart in Excel 2007

When you use the Name box to rename a chart in Microsoft Office Excel 2007, the chart is not renamed.

Note The Name box is located on the formula bar.

To work around this issue, use one of the following methods.

• Use the chart properties. To do this, follow these steps:
  1. Select the chart.
  2. Click the Layout tab under Chart Tools, and then click Properties.
  3. In the Chart Name box, type the name of the chart, and then press ENTER.
• Use a Microsoft Visual Basic for Applications (VBA) macro.
  
  The following code is an example of how to rename a chart in a VBA macro.
  
  Microsoft provides programming examples for illustration only, without warranty either expressed or implied. This includes, but is not limited to, the implied warranties of merchantability or fitness for a particular purpose. This article assumes that you are familiar with the programming language that is being demonstrated and with the tools that are used to create and to debug procedures. Microsoft support engineers can help explain the functionality of a particular procedure. However, they will not modify these examples to provide added functionality or construct procedures to meet your specific requirements.

  ActiveSheet.Shapes(1).name = chart_name