I have tried everything, i could change the language to english from tamil.Even i removed completly and reinstalled no chang at all still default language is tamil. any alternatives??? need support.
By English, do you mean American (US English) or English (GB English)? Depending on your version of LibO and operating system you may only have US English available unless you install the GB Language pack. The Language is the User Interface. The Locale Setting is for paper size, currency settings etc.
On my system Tamil is a CTL language; you can have a default language for all languages with a western like alphabet and way of writing and one for CTL languages like Arabic, Hebrew, Tamil and a lot more. If you navigate to Tools - Options - Language settings - Languages, you can turn off CTL and see if that helps.