You can copy-n-paste the contents of the current Profile folder into the Profile folder on the new PC, replacing whatever files are already in that "new" Profile. That does work, but it's not an official method endorsed by the Firefox developers. You could have a problem with an extension or two not being able to find its own data after doing that, but it's rare these days. You can not change the name of the Profile folder itself, otherwise Firefox won't recognize it and will create a new Profile and ignore the one with the wrong name. You need to paste the '''contents''' of the older Profile folder into the "new" Profile folder. http://support.mozilla.com/en-US/kb/Recovering+important+data+from+an+old+profile http://kb.mozillazine.org/Transferring_data_to_a_new_profile_-_Firefox https://support.mozilla.com/en-US/kb/Profiles#w_how-do-i-find-my-profile