Andrej Tozon's blog

With the latest RC release, Windows Live Writer introduced a couple of new languages for spell checking, including Slovenian. But there’s a catch – you won’t get any of them when you install the English version of Windows Live Essentials(a fancy name for all Live products, available through the same installer). Installing the English version will only get you English dictionaries, namely Australia, Canada, UK & US.

To get your Writer’s spell check your posts against your preferred language dictionary file, you have two options:

1. Download and run the Live Essentials installer for the language you want, then browse to the c:\Program Files\Windows Live\Writer\Dictionaries\ folder and get the files for your language (mssp3SL.dll and mssp3SL.lex for Slovenian language or equivalents for other languages). I installed this on my testing laptop so I didn’t have to uninstall the current version on my working machine. If you don’t have a spare machine, you’ll have to do a bunch of installs/uninstalls on one single machine to get everything back to where it was, plus gain your new dictionary files.

2. If you’re using Microsoft Office and already have a spell-checking option for your wanted language (either you installed localized version of some Office product or you installed additional Office Language Packs), the chances are you already have the necessary dictionary files on your machine. Browse to the C:\Program Files\Common Files\Microsoft Shared\Proof\ and look for the dictionary files (mssp3SL.dll and mssp3SL.lex or equivalent for your language (last two letters of the filename represent the language code). Copy those to Writer’s Dictionaries folder (c:\Program Files\Windows Live\Writer\Dictionaries\), restart the Writer and you’re good to go.
Note: I’m not 100% certain this is the case for any language available, but I found that for Slovenian language, both Office and Writer’s dictionary files were exactly the same! I also tested this with a couple of other dictionary files from my Office Proof folder and had no problems using them.

Windows Live Writer 2009 is currently a RC; the final release will hopefully make the process of adding additional language dictionaries easier by either:

• using Office dictionaries, if available
• releasing separate language pack add-ons

UPDATE: Windows Live Essentials RC, released a month, became RTW/final yesterday. It's the same version, so no need to upgrade if you already installed RC.