On this help page, you will find the following subjects :
To modify your password you must use the "Identification" hyperlink that is on the horizontal bar of "Your File" page. This will only be available once you access your file by entering your user ID and password. Once you select the hyperlink on the bar tick off "Modify your password" and click "Continue". Fill out every field on the "Modify your password" page and make sure to choose a new password with at least 6 characters (numbers or letters) then click on "Save".