afr.php - how to get rid of it

I use Firefox 3.6 and every time I went to certain web sites I'd get a request to download the afr.php file. Drove me nuts so I went to Google to see what it was and found many other Mac users and some Win7 users were having the same problem.

The advice was to clear the Firefox cache and return to the default skin. Tried that, didn't work.

Then I traced back the url address of the file and it reported:

http://q.u.d.cltomedia.info/delivery/afr.php

So I opened AddBlock and told it to block that address. Presto! It worked. No more requests to download afr.php.