“Why can’t I see my ad?” If you too have this question about AdWords ads. The Ads Diagnostic Tool can help you determine why your ad might not appear on a Google results page. Now, instead of showing just one reason why your ad may not appear, the Ads Diagnostic Tool lists multiple reasons — saving you time by listing everything that needs to be fixed in a single page of results.
What might these multiple reasons be? Consider a situation where your campaign has met its daily budget, causing your ad to stop showing for the day. Additionally, the specific keyword might be inactive for search. You’ll now be able to learn about these multiple issues immediately so you can adjust your budget settings and modify the keyword based on the Ads Diagnostic Tool results.
You can start using the Ads Diagnostic Tool now by pointing your mouse at the magnifying glass icon next to an individual keyword in your ad group or by going to your account’s ‘Tools’ page.[AdWords Team Blog]
Google, AdWords, AdWords Ads, Diagnostic Tools