Is the notes.ini file located on a server, or locally? At my previous work, we had experienced same problem with spellcheck (danish version) and the user.dic file. The problem was, when we tried to run a spellcheck, we got an error saying "Cannot add word to dictionary", followed by a Notes-crash.
We had windows2000 prof. installed on our workstations, and we ran Notes is from a networkdrive. I??ve set the variables to the networkdrive where the Notes-client was running.
"tmp = N:\temp" and "temp = N:\temp". (N being the networkdrive Notes was running from)
If I ran Notes from the N-drive, i created a temp-folder under that drive.
In Notes.ini - I found the string: "FileDlgDirectory=C:\temp" and I have replaced the C:\temp with N:\temp - to the networkdrive where Notes was running. It solved the spell-checking problems, and no Notes-crash followed.
I have tried some of the other solutions, this was the thing that worked for me. Maybe others can benefit from it.
Good luck ;o)