Why do my tests fail when run together, but pass individually?

Question

When I write a test in Visual Studio, I check that it works by saving, building and then running the test it in Nunit (right click on the test then run).

The test wo

Answer 1

I think you need to ensure, that you can log on for the second test, this might fail, because you are logged on already?

-> putting the logon in a set up method or (because it seems you are using the same user for both tests) even up to the fixture setup -> the logoff (if needed) might be put in the tear down method

     [SetUp]
     public void LaunchTest()
     {
        NavigateTo<LogonPage>().LogonAsCustomerAdministrator();
     }

     [TearDown]
     public void StopTest()
     {
        // logoff
     }
     [Test]
     public void Test1()
     {...}
     [Test]
     public void Test2()
     {...}

If there are delays in the DOM instead of a thread.sleep I recommend to use webdriver.wait in combination with conditions. The sleep might work in 80% and in others not. The wait polls until a timeout is reached which is more reliable and also readable. Here an example how I usually approach this:

    var webDriverWait = new WebDriverWait(webDriver, ..);
    webDriverWait.Until(d => d.FindElement(By.CssSelector(".."))
        .Displayed))