Unknown symbol in system tray hidden icons

[mdanp]

Hello, does anybody knows what could be this symbol, which appears in system tray hidden icons? It disappears when i try to hover mouse on it, but reappers in time and could be several.

 

[Bighorn]

Icons in the Notification Area, formerly System Tray, are usually associated with an installed program or a Windows App and usually named. RIght-click the Taskbar, choose Taskbar settings and the section about what gets shown. The icons can be shown or hidden as desired. Also click the little up arrow ^ to see more.

 

[Shintaro]

I would suggest that, when weird stuff happens, the first thing to do would be to run an "Offline virus scan".