I need to type in ‘en’ at the end of the address to make it work.
I also noticed that if I type the correct address in this post, the same error message pops up although the headline says ‘Dorico Pro Help’. https://www.steinberg.help/r/dorico-pro/5.1/en
*Okay, so only the link is visible after posting and not the light frame with blue text and greyed out text.
Please go to the General page of Preferences and choose a language other than English from the list of languages and click Apply, then go back and choose English again and click Apply once more. That should take care of it. Sorry for the inconvenience!