Hi Jonnyboy, I think that the AddOn maker doesn't working properly. It doesn't make the AddOn based on your default language. Here's my steps: 1. I choose "yes" when ask of Firefox is installed. 2. I choose "no" when asking if I like to use all of the defaults. 3. "yes" when asking if Firefox is on the default location (%PROGRAMFILES%\Mozilla Firefox). 4. Then, it ask me to locate the Profiles folder (%Appdata%\Mozilla\Firefox\Profiles\######). 5. Then I choose option 2 (Firefox 3.0). 6. After download and extract the Installer. 7. I create the Silent Installer only with the Custom Icon. I'm on Windows XP Professional SP3 Spanish and my Firefox 3.0 is based on the Spain language (es-ES) Another bug that I found is that the Silent installer creates two entries on the Add/Remove Programs, here's a screenshot: And it seems that is the "Mozilla Firefox (3.0)" entry that need to be removed, because when I chose "Remove" is just deletes it from the list.