Give me further information about your issue. What have you written is not enough. When do you receive that script error? What browser do you use? When occurs the error? Are you using Internet Explorer? Because that is a common problem of Internet Explorer or any other programme which makes use of Internet Explorer to display/do certain things. Also, a print screen would be useful.
When a Pop-up is blocked, it means that your browser blocked the website to open additional frames/pages etc. Usually, blocked Pop-ups are advertisements, but not always. The browser might be confused and actually block a legit, a normal page. Let's give you an example: if you are browsing a website, and you see a link "More information" and click it, the website may open that information in a separate window (to keep you on the same page) - which is a Pop-up.