I am guessing it is the result of a Login Item. To remove it please read macOS Sierra: If you think you have incompatible login items.
The information in that window is not legible. Try taking a screenshot of just the window itself, not the whole screen. To learn how to do that please read Take pictures of the screen on your Mac - Apple Support:
To take a picture of a window, press Shift-Command-4-Space bar, move the pointer over the window, then click.