If you have deleted the Firefox program and the files aren't in the recycle bin then your only option is to use an undelete utility like Recuva to recover your lost personal data. *Recuva: http://www.piriform.com/recuva ---- *https://support.mozilla.org/kb/Recovering+important+data+from+an+old+profile *http://kb.mozillazine.org/Transferring_data_to_a_new_profile_-_Firefox For the bookmarks it would be best to recover one of the JSON backups in the bookmarkbackups folder that have a name like this: bookmarks-####-##-##_xxxx.json (xxxx is the number of bookmarks in the file). A JSON backup is a text file and can easily be checked in a text editor or in the Scratchpad (Firefox/Tools > Web Developer) in Firefox (click the Pretty Print button to format the file for better readability).