Since you say " I have taken all the steps suggested by you " That is suppose to mean something to me. I have no idea what steps you took. https://support.mozilla.org/en-US/kb/profiles-where-firefox-stores-user-data and https://support.mozilla.org/en-US/kb/recover-lost-or-missing-bookmarks and https://support.mozilla.org/en-US/kb/profile-manager-create-and-remove- I have not had a chance to edit below yet Copy all and save all 1st before you delete) : If your Firefox profile folder includes a "places.sqlite.corrupt" file, one reported fix is to open the Firefox profile folder and, after closing Firefox completely, delete or rename the places.sqlite file and then rename "places.sqlite.corrupt" to "places.sqlite". (If you see any other places.sqlite* files, delete those as well, so that only one places.sqlite file remains.) It is possible that certain security or "cleanup" software (e.g., CCleaner) is causing the places.sqlite file corruption. It is also possible that Firefox was not closed properly, as might happen when your computer loses power with Firefox running, which can cause a corrupt places.sqlite file. Always make sure that you close Firefox properly (e.g., no Firefox processes in the Windows Task Manager) before shutting down the computer.