Windows 10 users will now be greeted with an unremovable advertisement in one of the operating system’s native apps.

Softpedia reported that the ad appears in the left sidebar of Windows 10’s Mail app for desktop and there is no way to hide it.

The banner was previously only seen in Insider builds of the operating system but has now been rolled out across consumer versions of the OS.

The ad contains only text, which reads “Get the free Outlook app on your phone”.

Clicking on it directs users to a website where they can download and install the Outlook mobile app.

No way to remove

Softpedia noted that the advert shows up even if the app has been installed on a device with the linked email account used.

The ad reportedly appears to users who have synced their Exchange, Gmail, and Outlook accounts to the desktop Mail app.

Microsoft confirmed that the ad cannot be removed and asked users to provide feedback on its inclusion.

“The ads within the app itself will be displayed regardless of which email address you use it with. It is not removable, but you can submit it as a suggestion within the Feedback Hub on Windows 10 here: https://msft.it/6012TVPXG,” Microsoft said.

Now read: Microsoft unveils new Windows logo and Office icons