Credit: Aggiornamenti Lumia

Microsoft has been incorporating ads in some versions of its own products since it introduced Windows 8. Now, there's a possibility that the built-in Microsoft Mail and Calendar apps could be next for the ad treatment.

According to a post and screen shot from AggiornamentiLumia.it, some Windows 10 Insider testers can see advertising banners in the Mail and Calendar apps. Aggiornamenti Lumia says users who are not Office 365 subscribers would be the ones who see the ads and the ads would be in the "Other" mail inbox, not Focused Inbox (for those who have Focused Inbox turned on, unlike haters of that feature like me).

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Microsoft already inserts Microsoft and third-party ads in Outlook.com for non-Office 365 subscribers (which I don't see because I use an ad blocker). There also have been ads in Microsoft's Games, News, Finance, Sports, Weather and Travel apps. Microsoft isn't the only company doing this. Google, Yahoo and other companies also include ads in their email and other first-party apps.

It's not clear if Microsoft has decided definitively to include banner ads in the Mail/Calendar app in an upcoming Windows 10 release or if the company is testing the concept and keeping its options open on this. I've asked Microsoft for comment. No word back so far.

Update: In response to reports about the Mail/Calendar ads, Microsoft's head of communications Frank Shaw tweeted that the advertising in Mail "feature" was experimental and is being turned off.

I have to admit, I really don't notice banner ads for the most part wherever they are (unless they are really obtrusive), so if Microsoft does include ads in Mail, I don't think I'll care a whole lot. But there are many others who are up in arms over this practice, as they feel they've paid for Windows either directly or indirectly as part of their PCs and thus shouldn't have to see ads.

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