Have you tried exporting to mp3 and using the Soundcloud uploader?
Often third party hosting sites such as Youtube, Soundcloud etc change their APIs - these are programs which software uses to communicate with and upload music, video etc - and these changes break the software which relies on them.
Your post has been hidden because a) this thread is already nearly nine years old and b) it is really irrelevant to a forum about Magix Audio products.
If you have a question about any Magix product please feel free to post it to the relevant area of the forums.