Hi Tanya,
We recently discovered that this problem is due to McAfee SiteAdvisor, a problem known by SmartBear. The expected page object is seen in TestComplete's object explorer but the page is not shown by IE.
SmartBear has been unable to find a permanent solution. The best known option is to disable SiteAdvisor, however, if there's no way to do this, you can use a workaround. The idea is to navigate to any page before the actual test steps by calling ToURL from the Sys.Browser("iexplore").BrowserWindow(0).Window("Frame Tab", "", 1).Tab("*").Window("Shell DocObject View", "", 1).Window("Internet Explorer_Server", "", 1) object. After that, pages start loading correctly, and tests run a expected.
In my case I had to clear some browser history to make it work.