Now, i want install it. But, i don't known. I try copy it and move to language folder in "dueling" : wwwroot\dueling\languages.

Please help me!

Thanks!

You are doing the right thing.Maybe you need to just reload the page and then select your prefered langaugae from admin section.

As far as i know Vietnamese is part of default language pack.Why do you need to install it?

My YAF version 1.9.1.8 ^^!

Maybe i will upgrade it.

Thanks!