Log on as an administrator.
XP
Click Start > Control Panel - Double click on the "Regional and Language Options"
Select the "Advanced" tab.
In "Language for non-Unicode programs", Select the desired language from the drop down menu (English).
Reboot the PC.
Vista
Click on the Start button, Click Control Panel
Click on "Clock, Language, and.." and then "Regional and Language Options"
Click on the "Administrative Options" tab, then in "Language for non-Unicode programs (system locale) " on "Change system locale" (If you are prompted for an administrator password or confirmation, type the password or provide confirmation.)
Select language your operating system (English) and then click OK
Reboot the PC (click Restart Now).