When you format or simply migrate your computer, you have many options to migrate Firefox. I prefer to copy system folders to keep Bookmarks, Saved Password and all Plug-ins and Themes.

To do a migration of XP computer to another XP, you need backup folders C:\Documents and Settings\%username%\Application Data\Mozilla & C:\Documents and Settings\%username%\Local Settings\Application Data\Mozilla. and just restore it at same place on the new Windows XP installation.

To migrate XP to Windows 7, follow this procedure :

1. Back up the XP folders : C:\Documents and Settings\%username%\Application Data\Mozilla & C:\Documents and Settings\%username%\Local Settings\Application Data\Mozilla.

NOTE : There are system folders. You need to show hidden and system folders to see them.

2. Install Windows 7.

3. Restore  C:\Documents and Settings\%username%\Local Settings\Application Data\Mozilla to C:\Users\%username%\AppData\Local\Mozilla  (When Windows ask you, go ahead to replace all files)

4.  Restore C:\Documents and Settings\%username%\Application Data\Mozilla to C:\Users\%username%\AppData\Roaming\Mozilla (When Windows ask you, go ahead to replace all files)

Done! You have now Firefox with all Bookmarks, Add-ons, and Saved Passwords…

This article was originally written by:
João Ricardo Wilde Neto
MCTS, MCITP, MCDST, MCT

Please note that English is my second language.
I am trying my best here, but just in case you read an odd sounding sentence every now and then, I hope you will pardon me.