Recently one of my users had a problem connecting to their Remote Web Workplace portal on their Windows Small Business Server 2003 (SBS 2003). I found that their browser at home had recently been upgraded to IE 10 which was the source of the problem. I think this has also been causing issues for Windows 8 users as well.
Two steps helped to fix this issue :
1. Click the "Compatibility View" button up on the address bar when you first hit your RWW site. (It's the icon that looks like a torn piece of paper.) Now try to connect again. If that doesn't work...
2. Add the domain name or IP address of your RWW site to the "Trusted Sites" list in your Internet Options in IE (click the little gear-shaped icon in the upper right corner and go to Internet Options. Then Security tab, then green Trusted Sites icon then Sites button). Restart IE and try again. This should fix the issue for you. You may need to let it re-install the ActiveX plug-in again.