Visual Studio Team Services sends "build failed" email when build succeeds - msbuild

Question

We're using Visual Studio Team Services for a project, and because we want to use continuous integration I set it up to build on each check-in, and to notify me when a build fails. Now, every time someone checks in code, I get an email that tells me the build failed:
Summary
Debug | Any CPU
3 error(s), 0 warning(s)
$/Foo/Bar.Foo/Bar.Foo.sln - 3 error(s), 0
warning(s)
C:\Program Files
(x86)\MSBuild\Microsoft\VisualStudio\v14.0\DNX\Microsoft.DNX.targets
(126): The Dnx Runtime package needs to be installed. See output
window for more details.
C:\Program Files
(x86)\MSBuild\Microsoft\VisualStudio\v14.0\DNX\Microsoft.DNX.targets
(126): The Dnx Runtime package needs to be installed. See output
window for more details.
C:\Program Files
(x86)\MSBuild\Microsoft\VisualStudio\v14.0\DNX\Microsoft.DNX.targets
(126): The Dnx Runtime package needs to be installed. See output
window for more details.
Other Errors
1 error(s)
Exception Message:
MSBuild error 1 has ended this build. You can find more specific
information about the cause of this error in above messages. (type
BuildProcessTerminateException) Exception Stack Trace: at
System.Activities.Statements.Throw.Execute(CodeActivityContext
context) at
System.Activities.CodeActivity.InternalExecute(ActivityInstance
instance, ActivityExecutor executor, BookmarkManager bookmarkManager)
at
System.Activities.Runtime.ActivityExecutor.ExecuteActivityWorkItem.ExecuteBody(ActivityExecutor
executor, BookmarkManager bookmarkManager, Location resultLocation)
When I go to visualstudio.com to check out the completed builds, the build in question is listed as "Succeeded". When I check the logs, everything is fine, and when I get a latest version and build locally, it also builds.
If I go to the "alerts" tab on the administration panel, I have one alert specified, with the following filters:
Team Project = [Current project]
AND Status = Failed
What's going on here?

Answer 1

I cannot say if it is safe to delete it since you don't know where it came from. And if you want to edit a XAML build definition, you need to do it from "Visual Studio\Team Explorer\Builds\XAML Build Definitions":
However, before you figure out if the XAML definition can be deleted, you can add one more filter in alert to set the alert to only track the build definition you want: