Sometimes a user's browser doesn't see where the user came from to your page. In such a case the pageview is assigned to "Direct traffic" source (sometimes also seen as "Dark traffic" source).
Here are a few reasons why it may happen:
- Mobile applications. Some smartphone apps are unable to pass information to a user's browser. Here are a few examples - suggestions applications as Google Now, messengers, advertisement blocks, mail applications, notifications, etc.
- Desktop applications. Such as mail clients, standalone messengers or social apps, PDF or other file readers also are unable to pass information to browsers.
- Favorites or bookmark links. There is no source information when a user opens a link from favorites or bookmarks bar in a browser.
- Direct input. Also, there is no source information when a user types, or copy-paste a link directly to the browser address bar.
- Insecure http:// protocol. When a user opens insecure http:// link to your page from secured (https://) website information about the source is not transferred.
- Browser. Also, it happens when a user uses an outdated browser or a browser with limited capabilities.
- VPN or Firewall protection may prevent a browser from tracking sources information.
- “no-referrers” feature. Also, a user can use “no-referrers” feature in the browser as it disables the ability to pass source information.
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