Once you have the webcast downloaded, follow these steps to view the Webcast:

1. Locate the downloaded webcast on your computer.
2. To Unzip, right click the file and select "Extract All...", then follow the onscreen instructions (this will only work if you have Windows XP or later. If you do not have the "Extract All..." drop down option then you will need to get a free extraction program such as Winzip or Winrar) 
3. After the webcast is unzipped you will have a new folder with the same name as the downloaded webcast.
4. Inside that folder find the file named scan.hta and double click on it. (You must have Internet Explorer 5.0 or later. Multipart webcasts will have a scan.hta file for each part.)