A possible cause is a problem with the file places.sqlite that stores the bookmarks and the history.

• http://kb.mozillazine.org/Bookmarks_history_and_toolbar_buttons_not_working_-_Firefox

hello and thank you for the response. unfortunately, it did not help. i have no other problems with anything other than not being able to bookmark new pages. the places.sqlite is not locked. i tried backing up and restoring my current bookmarks - this did not help. any other suggestions?

well, with further "analysis" - it's only certain web pages that won't bookmark... maybe it's the actual website? but the same site WILL bookmark with another browser. so, i don't know....

You did delete all places files in the Firefox Profile Folder?

• http://kb.mozillazine.org/Profile_folder_-_Firefox
• Help > Troubleshooting Information > Profile Directory: Open Containing Folder

i didn't. i only backed up and restored the bookmarks. i read in some of the stuff about deleting places.sqlite and rebuilding it - but i was really hoping to avoid that... do you think if i exported my bookmarks (to not lose them), uninstalled firefox, then reinstalled it it would solve the problem?

Firefox should import the bookmarks automatically from the latest JSON backup in the bookmarkbackups folder if you delete places.sqlite and the other places files, so you shouldn't lose the bookmarks.
You will lose the browsing history.

See also:

• http://kb.mozillazine.org/Backing_up_and_restoring_bookmarks_-_Firefox
• http://kb.mozillazine.org/Profile_backup