Change the Display Language
By default, the PowerPivot window uses the same language as Microsoft Excel. However, you can change the language that is used to display PowerPivot menus and error messages.
To change the display language
In the Excel window, click the PowerPivot tab, and in the Options group, click Settings.
In the PowerPivot Options & Diagnostics dialog box, click the Language tab.
The Current Language box shows the language that is currently used, and the Collation box shows the sorting order that is used.
In the Language Options box, click the down arrow and select the language that you want to use for PowerPivot menus and error messages. Click OK.
If you are currently using a different language for PowerPivot and want to use the same language as Excel, select Match Excel Language.
Close the PowerPivot window and the Excel workbook, and restart Excel.