Help: How to solve upload errors in dtube?

I need help!

I'm clearly doing something wrong and I can't figure out what it is. I keep getting this error when trying to submit a video on d.tube.

I am not able to upload a snapshot either. I can open the upload window, but whatever image I select, doesn't overwrite the one that is already there.

Am I missing some entries?

When I click the submit button, it doesn't react. However I do see from the little wheel on top, that something is happening. But after a few minutes, the red error button appears again...

I decided to post this here, because I know that there are others who have trouble uploading videos to d.tube, too. I haven't found a solution for this by searching - I only found upload tutorials from last year, but they didn't address the potential errors and how to fix them.

Hopefully Hive account@dtube Hive account@heimindanger or other knowledgeable people can offer some solutions in the comments.

Thank you!