Where Is This Being Addended to Our Page File Names?

[lbohen]

I have worked over the last several months to eliminate duplicate page titles at our site. Below is one situation that I need your advice on.

Google Webmaster Tools is reporting several of our pages with
duplicate title such as this one:

This is a valid page at our Web store:

http://www.audiobooksonline.com/159179126X.html

This is an invalid page that Google says is a duplicate of the one above: http://www.audiobooksonline.com/15​917​912​6X.​htm​l?g​dft​rk=​gdf​V21​38_​a_7​c17​7_a​_7c​432​_a_​7c9​781​591​791​263

Where might the code ?gdftrk=.... be coming from?

How to get rid of it?

[MattAntonino]

I'm guessing that in ShopSite 11, that's your affiliate tracking code?

http://shopsite.com/popups/associate.html

I found another site using ShopSite that uses this Robots.txt to block it:

Robots.txt:  User-agent: * 
Disallow: /dev/ 
Disallow: /dev18/ 
Disallow: /devupgraded/ 
Disallow: /staging/ 
Disallow: /rss/catalog/ 
Disallow: /skin 
Disallow: /shopsite 
Disallow: /?dir 
Disallow: /?order 
Disallow: /?mode 
Disallow: /?limit 
Disallow: /?price 
Disallow: /?utm 
Disallow: /?gdftrk 
Disallow: /?gclid 
Disallow: /*?SID