How to Change Office 2010 From German to Englishby Chris Miksen
Microsoft Office is used internationally, so Microsoft made it a point to include many different language packs with every Office program. If you're using the German language pack, Microsoft Office will not recognize anything typed in English, unless you change the preferred language. Changing the language in one Office program changes the default language in all Office programs within the same software suite.
Launch the Microsoft Office program you wish to use.
Click "File" at the top left of the screen. Click the "Options" button above the "Exit" button.
Select "Language." If English is not available in the "Editing Language" box, click the "Add additional editing languages" drop-down menu. Select "English" and click "Add."
Select "English" in the "Editing Language" box and click "Set as Default." Click "OK" when a message appears and informs you that you must restart Microsoft Office for the change to take place. The change effects all Microsoft Office products installed on your computer.
Restart the Microsoft Office program to begin using the English language.