Nice job tracking down where the cookies came from.
You can set up Firefox to block unwanted and unneeded cookies this way:
Click on Tools
Make sure there is a check mark by "Accept Cookies from Sites." Then in the box just below, make sure the window says "Ask me every time."
What this will do is that every time a site wants to put a cookie on your computer, a little window will pop up asking you if you want to accept it. The first time it shows up, click on "Show details". From then on, except when you reinstall Firefox or in some instances update it, the details will always be shown. There you can see who wants to put it on your computer and whether it is a session cookie or a permanent cookie.
You can add the site to your black list or white list by putting a check mark Use my choice for all cookies from this site
and clicking on Deny
which adds it to the black list or Allow for session
. The latter choice means that any permanent cookies will stay on your computer until they expire or you delete them. The former choice means that the cookies will always go away when you close your browser. Either way, the sites will be added to the white list.
You can see what cookies are installed by clicking on the Show Cookies
button on the privacy screen where you set the cookie options. When you click on Exceptions
you will see the list of sites blocked from or permitted to set cookies. You can manually add sites to the block or allow list here, and you can also remove sites from the list.
Security programs such as SpywareBlaster will add many sites to the block list to protect you from tracking cookies.