Syntax Error:

_ When I visit <a href="http://www.mapquest.com" target="_blank">www.mapquest.com</a> the following error pop up:

"A runtime error has occurred."
Do you wish to debug?
Line: 5
Error: syntax error

_ After click on the yes button on the debug error window an application similar to Visual Basic appear with an error message:
"Microsoft Development Environment"
Source code is not available for the current statement.

I am using Internet Explorer version 5.50.452.1800CO. Do I have to upgrade to Internet Emplorer version 6 to fix it? This error is not happening when I visit a different websites. thanks for all your help!

open IE 5.5
go to tools / internet options / advanced

check disable script debugging and the message not appear anymore. My supervisors computer was doing this on any and every page. fixed it in a jiffy.