There is a tool known as MozBackup that not only backs up all your add-ons, profiles, and passwords, but also takes care of stored cookies, history, the download file list, general settings, certificate etc. Also this tool is dead simple to use. You need to download it to your computer. It is available in portable version also.
Once the download is complete, double click on the MozBackup-1.4.10-EN file to run the tool.
On the welcome screen, click Next.

Now select the Backup a profile option, as you are creating a backup. Later if you want to restore a profile then you have to choose Restore a profile. In addition to Firefox, you can also backup Mozilla Thunderbird and other Mozilla portable applications using this tool. Select Mozilla Firefox 3.6.12 (en-US) and click Next.

It will ask you to select the profile. If you created any new profiles, they will be shown on the interface. Otherwise, it will display only the default profile. You can select the backup location by clicking the Browse button. After selecting the profile for which you want to create a backup, click Next.

It also provides you the ability to encrypt the backup file. You can password protect it by clicking the Yes button.

Enter the password in the required fields and click OK.

Now select the items you want to backup (Check the boxes next to the item name). There are options to create backups of General settings, Bookmarks, History, Extensions, Saved passwords, Saved form details, Downloaded file list, Certificates, etc. Check the boxes and click Next.

It will take a few seconds to create a backup. After the process is complete, click Finish.

The backup file will be saved in your computer in .pcv format. You can transfer this file to a USB drive or CD and keep it in a safe place for later use. If you want to restore your Firefox items using the backup file, then you have to run this tool again on your computer and select Restore a Profile instead of Backup a profile.
You can download MozBackup here.
~Himanshu Yadav

