From: John H Meyers on
Re X-Eudora-Option links, instructions for which appear
in the first "NOTE" of any Release Notes, or at:
http://www.eudora.com/download/eudora/windows/7.1/RelNotes.txt

Incidentally, even in Thunderbird, or in any of my installed web browsers
(Opera, Firefox, Safari, or Internet Explorer),
clicking any of these "URL-like" links (registered as a "protocol")
causes Eudora to be called to "open" them,
and the very same option-setting dialog then pops up in Eudora.

You can find planty of these "links" to try in web browsers
at this web page, which also documents many (but not all) of the options:

http://www.eudora.com/techsupport/ini.html

For a complete list of all recognized options in 7.1,
compiled by Jim Higgins, see:

http://groups.google.com/group/comp.mail.eudora.ms-windows/msg/a4fb742b3f152bf7

In most cases, as you might surmise, the end result is to store or adjust
the option name which follows the colon [:] of the "protocol,"
along with the value being set, in file Eudora.ini,
most often in the main [Settings] section
(with a few exceptions that are stored elsewhere).

These "links" permit you to perform this while Eudora is running,
and also to view default values and "help" for those which have help;
otherwise you would have to terminate Eudora and manually edit Eudora.ini

Javascript-based Mozilla-related programs
often recognize an about:config URL ( opera:config in Opera )
to access and set every possible internal option,
so it should not seem so strange that Eudora
has a built-in mechanism that can also set any possible internal option,
provided you save a copy of Jim Higgins' list from the above location,
as a message in some Eudora mailbox.

Most Eudora options take effect immediately,
though a very few require restarting Eudora.

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