This warning is for the programmer, not you. Had the programmer paid attention, you wouldn’t be seeing this message. But you can keep it from appearing again. Just, remove the check mark by the item Always Display This Message When a Page Contains Errors.
To ensure that errors don’t appear in the future, follow these steps in Internet Explorer:
Choose the command Internet Options from the bottom of the Tools button menu.
Click the Advanced tab in the Internet Options dialog box.
You see three items to check in the list, all found beneath the Browsing heading.
Place a check mark by the item Disable Script Debugging (Internet Explorer).
Place a check mark by the item Disable Script Debugging (Other).
Remove the check mark by the item Display a Notification about Every Script Error.
Click OK to close the Internet Options dialog box.
Suppressing the error message doesn’t remove the error from the page. The error is still there. But it’s up to the programmer or web page designer, not you, to fix the problem.