can anyone tell me what is here wrong:
The picture is missing - that's wrong.
Probably you tried to add the picture via cut and paste. This looks good, but only until you press the "Post" button. The picture will vanish then. The Forum software used here since a year really sucks.
You have to use the camera icon in the top menu to insert a pic in the text or you may use the "Durchsuchen" button to attach a file.
BTW, its always better to attach your worksheet rather than just posting a picture.