I researched this problem but all the tutorials I found didn't work for me. Probably because I couldn't find a single one that was dedicated to Windows users?
I am having trouble to spell check my current latex document in texlipse. I downloaded the en.dict here (http://sourceforge.net/projects/texlipse/files/dictionaries/) put it into some folder and pointed the texlipse spell checker to that folder (just the folder. the file itself wasn't shown in the eclipse browser) under Windows -> Preferences -> Texlipse -> Spell Checker -> Directory for main dictionaries. Furthermore I enabled latex spell checking under ... -> General -> Editors -> Text editors -> spelling.
Then I set up the project again to make sure it is set to "en" as the projects language, but still. nothing gets highlighted and if I click on latex -> Spell check, I get the error:
running: null
Error running spell checker