Just wanted to post something about a bug I found when OpenSTA crashes:

When I was recording a script OpenSTA crashed and then I couldn't get to any sites. I found that the program changed the browser connection settings to use itself as a proxy on port 81. When it crashed it never changed it back to the original settings. To fix this simply click on "Tools" in IE. Then choose the "Connection" tab, click on the "LAN Settings..." button and then uncheck the proxy settings or set them back to their original settings.

Hope this helps, it drove me crazy...