In windows Server 2003, Internet Explorer Enhanced Security is an extra layer of protection when user going to surfing the Internet but most of the people are not want to keep this security so Microsoft allow you to disable this security.
Step by Step
Click on Start and then go to Settings and then click on Control Panel.
Now click on Add/Remove Programs icon.
In Add or Remove Programs, Click on Add/Remove Windows Components.
Now after few seconds the window wills pop-up. Uncheck to Internet Explorer Enhanced Security Configuration option. Then press Next and then Finish.