Google AdSense is now warning some publishers that their revenue is at risk because they have not uploaded an ads.txt file to the site's root domain. Google says, "To avoid a serious revenue impact, download an ads.txt file and then upload the file to the root domain of each site."

You may see a warning at the top of your Google AdSense console stating "Earnings at risk - You need to resolve some issues with ads.txt to avoid a serious impact on your revenue" Then two action buttons, one for "Fix it now" and one for "Learn more"

Here is a screenshot (click to enlarge):

Then, when you click on it, it shows you this warning that says "To avoid severe revenue impact, upload an ads.txt file and then upload the file to the root level domain of each site." "Updating the changes may take a few days. If you are using another ad network, don't forget to add that network to the ads.txt file. See the ads.txt guide for more details," Google adds:

Here is a screenshot (click to enlarge):

I barely use AdSense on this site, so I'm not worried but someone who depends on AdSense for income, it can be scary.

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