Can you please be more specific than that? Thanks.

see if this helpful : How do I use the Firefox spell checker?

thank you

I just had all my machines update to 14.0.1 and it has sporadic access to the spell checking feature. When it first came up today (after a full reboot) it had no spellcheck facilities at all.Nothing I typed was checked. I tried everything I could do one at a time (I was a senior IT contractor for years). I ever tried turning off all my addons using "SAFE" mode for FIREFOX (no change).

Then as I was typing this message (with no spell check) suddenly the spell checking turned on. SO I retyped the message with NEW information. Mind you, I had changed NOTHING in my FIREFOX settings.

This means the error is what we used to call "flakey" (our technical terminology for an intermittent bug without any apparent simple cause). In my experience this usually points to either :

1) convoluted code, often from being created rapidly without solid and well understood logic (the things we are willing to do to make a deadline....) often resulting in variables that are left set improperly, that resolve once the program has been running (you have to hit the right piece of code for the bug to resolve)

or

2) an untraceable compiler error (which suck big time) which tend to magically appear (having nothing to do with the actual code quality) and tend to go away from things as little change as the addition of a single blank line of code, or the removal of a remark. I hate those with a passion

Maybe replies to BarleySinger's post should go in this new thread: Firefox 14.0.1 has a spell checking error./ bug in the code

The main reasons for the spell checker no working is due to either not having a dictionary language selected or due to using one of the few Extensions that interferes with the spellchecker.

The spellchecker works fine on default clean install of Firefox 14.0.1 en-US on Windows, Mac and Linux.

For example in http://forums.mozillazine.org/viewtopic.php?f=38&t=2519753 it was the "Multi Links" extension that made the spellchecker not work on Firefox 14.0.1.