When you reset Firefox then a new profile is created and some personal data (bookmarks, history, cookies, passwords, form data) is automatically imported and the current profile folder will be moved to the desktop to an "Old Firefox Data" folder. Installed extensions and other customizations (toolbars, prefs) that you have made are lost and need to be redone.

You can copy the cookies.sqlite file from the "Old Firefox Data" folder on the desktop to the current Firefox profile folder. You can use this button to go to the currently used Firefox profile folder:

• Help > Troubleshooting Information > Profile Directory: Show Folder (Linux: Open Directory; Mac: Show in Finder)
• http://kb.mozillazine.org/Profile_folder_-_Firefox

See also:

• https://support.mozilla.org/kb/Recovering+important+data+from+an+old+profile
• http://kb.mozillazine.org/Transferring_data_to_a_new_profile_-_Firefox

Thanks. However it didn't restore what I was trying to, but that doesn't really bother me. Restored everything else.

Note that you need to make sure to remove all cookies.sqlite files (-wal and -shm) when present with Firefox closed. It is possible what a server invalidates cookies if they detect changes.

Did you check the Cookie Manager?