The cause may be a too large file or an incorrect data format.
Solution:
- Please use a file size of up to a maximum 500 KB
and / or
- one of the following data formats: *.JPG, *.PNG or *.GIF.
If necessary, your image will be adapted proportionally in height and width.
If the above mentioned requirements are fulfilled and the image is still not uploaded / displayed, then a browser change (e.g. Google Chrome, Internet Explorer, Mozilla Firefox) can solve the problem.