https://support.mozilla.com/en-US/kb/Lost+Bookmarks

AFAIK, Firefox doesn't need to contact a server for anything related to bookmarks, unless you have an addon that modifies standard Firefox behavior or adds features to Firefox.

I see by your UserAgent that you have the Google Toolbar extension installed, are you using the Google Bookmarks feature? Maybe that is your problem, Google bookmarks attempting to "call home"?

What else do you have installed that might be causing that problem? Open up Help > Troubleshooting Information and hit the Copy all to clipboard, then paste that information into the Post a Reply box in this thread. That will give us a listing of all you installed addons.

try going to this link, then take it from there. if you can drag the google bookmark icon to your toolbar. it worked for me. http://googlebookmarks.com/