Are you aware that Firefox stores its' own bookmarks in the places.sqlite file in the Firefox Profile folder? It doesn't use a file or folder named Favorites.

See these support articles:
http://support.mozilla.com/en-us/kb/Profiles#How_to_find_your_profile

http://support.mozilla.com/en-US/kb/Recovering+important+data+from+an+old+profile

Thank you for your help.

Useless trying to RUN: places.sqlite, or D:\places.sqlite, or %APPDATA%\Mozilla\Firefox\Profiles\, or D:\%APPDATA%\Mozilla\Firefox\Profiles\

A complete search of D: Drive yielded: nsBrowserGlue (Java Script), and: PlacesDBUtils.jsm (JSM File) I opened the latter with notepad and got the GNU, etc., but no usable links.

Opening the D: Firefox container "zu2u04mk.default" > bookmarkbackups. -This has five bookmarks.json Files, but C: Drive also has these same files with same total size, so I don't believe these are the bookmarks I want.

Now consider Firefox bookmarks to be transitory. Will save any important links to Internet Explorer Favorites from now on. Thanks again.

If those JSON backups are the same size on both drives, my guess is that you had more than one Firefox Profile on D:\ and your bookmarks are in another Profile than the one you found.

"Now consider Firefox bookmarks to be transitory. Will save any important links to Internet Explorer Favorites from now on."
LOL, any file in Windows is "transitory" if the user doesn't back it up!

I think that Firefox is a very useful browser, but that it would be great if the Bookmarks were automatically stored in a folder outside the Program (like the "Downloads" folder that Firefox creates in "My Documents"). -That is the one great feature of that lump of concrete called: "Internet Explorer 6".

What difference does it make where a program stores its' users data?
For the average user, and the "dual boot" users who know what they're doing, Firefox works fine - no lost bookmarks.

IE only allows one browser version to be installed at the time. You can have as many Firefox versions installed and even have them open at the same time. In such a case you do not want to have the same personal data in each browser instance even if Firefox would allow that via file sharing and closing files after updating. Windows with its drive letters may not always be very suited to use the same profile folder in a multi boot environment.

See also http://kb.mozillazine.org/Roaming_profiles

Cor-El totally got it! Everything on the slave drive (D:) is completely accessible from Master Boot Drive C:, --except the profiles stored in Firefox on D: Drive. Accessing those profiles is not possible unless logged in to D. I exported the Bookmarks from the Firefox install located on D, while booted in C, and got only the bookmarks from C. I considered removing Firefox from C Drive to see if that would render only the bookmarks from D, but decided that would only result in a blank page of bookmarks. That Link from Cor-El probably holds the answer for me. I therefore consider this solved. Thank you so much.

I still think "that it would be great if the Bookmarks were automatically stored in a folder outside the Program", the key words here being: "Automatically & Outside". That Link: (http://kb.mozillazine.org/Roaming_profiles) just might offer me the next best solution to that. Thanks to all.