Getting error when trying to run watir-webdriver/cucumber on windows

Question

I am getting the following error when trying to run my cucumber/watir-webdriver/ruby tests.

Failed to navigate to http://test.domain.com. This usually means that a call to COM method [WebBrowser2::Navigate2() failed. (Selenium::Webdriver::Error::UnknownError)

It works fine if I run it in firefox. Just getting this issue in IE.

Any idea what could be causing this? Thanks!