There just might be a workaround for this. I found a German language (for ME) in the Windows Update site, when I installed it I was able to change the Language I wanted to work in to German. It also changes Outlook Express to the chosen language.
choose 'scan for updates' then look at all updates for your computer, there should be a multitude of Language options. If this is the same in XP you will be able to choose English on your Spanish OS and when you activate this all your menus and dialog boxes should be in English including OE. You should have the Spanish Retailer do this for you unless you have a command of Spanish.
Perhaps someone using using XP could have a look at the windows update page and advise if these Language options are available for XP???
English versions of XP are freely available from wholesalers here, or imported from the UK (I do both) - so you should be able to get a PC with and English XP on it with no problems. Likewise for Office, Works, etc.
Otherwise, although you can get parts of an OS to come up in English, you cannot "change" to English as the main language for the OS.
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