I posted this as a reply to another question, but I figured it would be of
interest as a new thread to everyone who wants to switch language with their
copy of Vista:
You can install MUI languages on Ultimate and Enterprise, no matter where
Vista or the PC with Vista was purchased. MUI languages are the main Vista
languages, meaning Microsoft has officially released Vista in these languages.
The list is available here:
You can install LIP languages packs on all versions of Vista (including
Vista Home... I know, I tried!)
Problem with LIPs: first they are or will be languages that are not MUI
languages and second they have to be installed on a dedicated MUI language
(meaning you cannot install Catalan on English, but you can on a French or
The list of potential LIPs is available here:
Consequence: You will not be able to install French (a MUI language) on
English (another MUI language) on Vista Home, Home Premium or Business.
Also, I could only find two LIP packs available for Vista (Catalan and
Hindi). Since I have an English Vista, I could not install Catalan - which
requires French or Spanish - but was able to install Hindi (which I do not
As a side note, the Hindi screens were a mix of Hindi and English at a ratio
of 70/30, with help files all in English! LIPs are not 100% clean. And if
they were 100% clean, they would become MUI, and Microsoft would not make
them available as LIPs (my guess).