I have two files that I managed to restore from a Firefox installation under Windows XP. The first one is urlclassifier3.sqlite and the second one is urlclassifier.pset
Bookmarks are held in file places.sqlite
, not urlclassifier. You can try to replace the file in your current installation with that. Make sure Firefox is closed. If that doesn't work:
You might want to install the Firefox addon "SQLite Manager" and then use the addon (use the Alt key to open the addon menu in Firefox) to open the file places.sqlite from your old install. Right click Tables -> moz_bookmarke on the left hand side and click "export table"
Export your table as XML or SQL and then open file places.sqlite from your current install and click Database -> Import Table and import it in the similiar same way you exported.