UTF8 Error when adding Adrotate Widget

hello,

after the last update i had to remove Adrotate widgets from my Blog. Everytime i insert the Adrotate Widget or the Tag on a Text HTML widget, i got an error UTF-8 on my whole page. All the pages of my blog become with encoding problems

Another AdRotate Group is running in post insertion with no problem. The problem is directly related to adrotate on a widget. Attention – Even when i add an Adrotate widget without any option of advert ID or Group Id choosen , the error repeats.