Error while fetching from DOI

Thanks you for the reply. But I am getting the same message even if i installed the latest version. See the screenshot:


The black one is Jabref 4.3, the red one is the latest one.

Another thing which i noticed is that while installing Jabref 5, it did not ask to create a start folder in start menu and hence I cannot search it in the start menu. Why is it behaving in this fashion? Am I doing anything wrong?
Thanks in advance…