This is the direct link to download the Dell Webcam Central progam. This is the full version of the program and not an update. The software will install Webcam Central version 1.40.05  Please note that the "Driver Details" page will list this as for a Dell SX2210 monitor.  This is the correct link for the Webcam Central software for all notebook systems shown under the "Compatibility" drop-down. 

http://ftp.us.dell.com/monitors/Dell_SX2210-Monitor_Webcam%20SW%20RC1.1_%20R230103.exe

Some XPS Models need Windows 7 drivers downloaded from Drivers & Downloads. If you have an XPS laptop please visit the Drivers & Downloads website, enter your service tag number, and look for your webcam drivers under the header INPUT.

If you'd like to view the knowledge base article to walk you through the process you can view it here

If you need assistance installing the Webcam Central program please view the You Tube video