Steve Clayton blogged about how to get a UK English dictionary working for Windows Live Writer, however this trick doesn't work for Windows Live Mail Desktop. If you have Microsoft Office though, you can get the UK English, and any other installed dictionaries working.
- Copy all the files from
%ProgramFiles%\Common Files\microsoft shared\Proof
to
%ProgramFiles%\Windows Live\Mail\Proof\prf0009\2
- Edit the file %ProgramFiles%\Windows Live\Mail\Proof\prf0009\spell.ini. Change
Lang=1033
to
Lang=2057
- Restart Windows Live Mail and your dictionary should now be in English (UK). You can also switch to any other dictionaries installed with Office in Tools / Options / Dictionaries.