How are your tests structured? What type of test are you using? A coded unit test or a WebAii test (i.e. a .aii file)?
If you're using a pure coded test you need to include the tear down code (and you don't need an ActiveBrowser.Close(); since our tear down code does this for you). Our standard tear down code looks like this:
// Use TestCleanup to run code after each test has run
// Place any additional cleanup here
#region WebAii CleanUp
// Shuts down WebAii manager and closes all browsers currently running
// after each test. This call is ignored if recycleBrowser is set
//Use ClassCleanup to run code after all tests in a class have run
// This will shut down all browsers if
// recycleBrowser is turned on. Else
// will do nothing.
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