In June, we announced ( that Chrome will begin pausing many Flash ads by default to improve performance for users. This change is scheduled to start rolling out on September 1, 2015. 

Most Flash ads uploaded to AdWords are automatically converted to HTML5. To ensure your ads continue to show on the Google Display Network, please follow these steps before September 1:

1) Identify any Flash ads in your account that aren’t eligible for automatic conversion: 
2) Convert these ads to HTML5:
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