Resolved Taskbar question

Hello, I've got a taskbar question.

Usually when I open a program or a web page, there is a corresponding icon appearing on the taskbar at the bottom of the screen.
However, now I've got two corresponding icons on my taskbar, one on the left next to the quick launch icons; on the right next to the system icons.

I've tried to lock/unlock taskbar, moving around the icons, but nothing seems to help.

I would greatly appreciate any help.

 

Thanks! Problem solved!