If you have subscribed to the URL Defense (Phish protection feature) or are currently in proof of concept you may wish to run tests to check service effectiveness. Recommended practice would be to use EICAR for testing to verify that the system is correctly configured and is actively quarantining malicious content.
What does EICAR stand for?
European Institute for Computer Antivirus Research.
How do I download the test file?
You can download the test file here – http://2016.eicar.org/86-0-Intended-use.html