One of the many changes to XP is the addition of a pop-up blocker. To allow eHCS web application to open pop-up windows such as calendars or appointment schedule locations, when Internet Explorer tells you that the pop-up is not allowed, click the bar on the explorer window and click allow pop-ups for our web server.
If you are running Windows XP operating system, you will need to update your OS to Service Pack 2 (SP2), if you have not done so to date.
If you are not running Windows XP operating system Service Pack 2 (SP2), check to see whether MSN, YAHOO, Earthlink, Google, or any other third-party tool bar has been installed on your Internet Explorer (IE) tool bar.
There is more than likely a pop-up blocker available, which is causeing your pop-up windows to (a) not appear or (b) pop-up as a blank window.
Please ask your network administrator to locate the toolbar's pop-up blocker option and set the blocker to always allow pop-ups from this site.