Thanks Tuan, that fixed it! Download of update successful.
Tuan Pham Ngoc wrote: Hi Sven
I think maybe that Download ID was used for a different website (maybe on a sub-domain or on your dev site). Please generate and use a new Download ID (you can generate multiple Download IDs) and check it again. If the error still happens, submit a support ticket sending us super admin account of your site so that I can check to see why update does not work and get it sorted