I just upgraded to Lyx 2.1.4 from Lyx 2.1.3 and the spellchecker does not work -- it asks if I want to start from the beginning and then closes like it found no errors. I am using Windows 7 with a clean default install of Lyx. Any ideas on how to get the spellchecker working again?
I think I found the problem. First point the path of hunspell to your equivalent folder:
C:\Program Files (x86)\LyX 2.1\Resources\dicts
Then, it is an incorrect or corrupted en_US.aff/dic files. I downloaded another version from hunspell project:
and overwrite ir in the dicts folder, that worked for me.
I had a similar problem which I managed to fix by going into Document -> Settings -> Language and then changing the default, which was English, to English (UK).
The UK solution works, but if you want any other language like US English, this is the way to fix it:
First, find the hunspell directory with all the dictionary (dic and aff) files in it. For me, it was "C:\Program Files (x86)\MiKTeX 2.9\hunspell\dicts"
Next, point Tools > Preferences > Paths > Hunspell Dictionaries text box to this directory.
Lastly, restart Lyx.
I was able to find a solution to this problem. Copy your dic and aff files from where they are now (C:\Program Files (x86)\LyX 2.1\Resources\dicts, usually), to a new folder, C:\dicts (or similar), and then change the path in lyx accordingly, and reconfigure lyx.
I don't know exactly why this works though.