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Changing the Reply Header in Thunderbird

To change the reply header in Thunderbird:

1) Create a user.js file in the the profile folder for Thunderbird. This can be found at C:\Documents and Settings\[User Name]\Application Data\Thunderbird\Profiles\[Profile Name]

2) Add the following to the user.js file

// Change the reply header
// 0 – No Reply-Text
// 1 – “[Author] wrote:”
// 2 – “On [date] [author] wrote:”
// 3 – User-defined reply header. Use the prefs below in conjuction with this:
user_pref(“mailnews.reply_header_type”, 3);

// If you set 3 for the pref above then you may set the following prefs.
user_pref(“mailnews.reply_header_authorwrote”, “%s said the following”);
user_pref(“mailnews.reply_header_ondate”, “on %s”);
user_pref(“mailnews.reply_header_separator”, ” “);
user_pref(“mailnews.reply_header_colon”, “:”);
// The end result will be [authorwrote][separator][ondate][colon]


1) Default installation locations for Thunderbird
2) Base OS is Windows XP


For more information, visit Mozilla Thunderbird: Tips and Tricks