Possibly because the text you are typing has been marked as being one
language, while your custom dictionary has been marked as being another
language. Try this: Click on Tools | Options | Spelling & Grammar | Custom
Dictionaries. Is the default dictionary file listed as an indented item
under a language name? If so, click once on the default dictionary, then
click on Modify, and set the language to "All languages".

"Troubled!!" wrote:

Hi,

Can anyone tell me how I can bring back the add button? I have been using
word 2000 for some time and when I have words that are not in the dictionary
I used to be able to click on add. But no more, the add button has been
greyed out.

Thanks

Eric.