Recent content by taskbar

taskbar just freezes at the first time after reboot and also when i close the browser,taskbar returns normally

Hi everyone i just joined the forum. The problem is when i start the computer and then open a browser(IE or Chrome),my taskbar gets frozen and it doesnt respond for a while(1 or 2 mins.) i wonder what makes this? Could you help me ? note: im using Ultimate version. Thank you