Note:
"UserDictionary.txt" is a text file that uses Unicode, not ANSI. It starts with the bytes 0xFF 0xFE and contains Unicode characters only. In recent Windows versions, you can edit that file with Notepad.
The format is simple: one word per line; no spaces are allowed; any line that begins with the "//" characters (that is, commented out) will be ignored. The user dictionary is case insensitive.