Have you installed any toolbar (Coupon Bar)/software related to Coupons? Is yes, refer method 2 to uninstall it.
I suggest you to perform the following method.
Method 1: Try starting Internet Explorer without add-ons to see if the problem goes away. Here's how:
1.Click the Start button,
2.Click All Programs,
4.Click System Tools
5.Click Internet Explorer (No Add-ons).
If disabling all add-ons solves the problem, you might want to disable all add-ons and then turn on add-ons only as you need them. This will allow you to figure out which add-on is causing the problem. For more information about add-ons, see