Add Bookmark dialog doesn't work (Firefox)
Corrupt localstore.rdf file
A corrupt localstore.rdf file in your profile folder can cause this problem. Either of the solutions below will fix it, but you will lose any toolbar customizations you might have made .
Firefox 1.5 or later: Exit Firefox completely and start it in Safe Mode. A window called Firefox Safe Mode with some troubleshooting options will appear. Select the option "Reset toolbars and controls" and choose "Make Changes and Restart".
All Firefox versions: Exit Firefox completely and then open the profile folder and delete the file "localstore.rdf". Make sure to delete the "localstore.rdf" file in the profile folder and not the program files copy (in Windows, the profile folder may be hidden).
The Bookmark Duplicate Detector extension has been reported to result in failure of the Add Bookmark dialog in Firefox. If updating the extension doesn't help you should uninstall it.
I run WindowsXP home edition and use Firefox. For the past week I haven't been able to add any bookmarks. The dialog box shows up but when I click ok it doesn't add the page to designated folder. I tried adding bookmarks to IE and that works but not with FF. Any suggestions? Thanks.