If you using Windows then go to "Network and Sharing Center", then click on "Change adapter settings", and check if the "WorldVPN" driver is still installed. Then go to "Device Manager", then "Network adapters" and find "WorldVPN adapter", right click, uninstall adapter, and restart your computer. If your internet connection is still slow, reset your "Internet Explorer" settings.
I hope that works for you, if your problem is still not resolved.