We are at the latest (v0.43.4.2), running on our own server.
I saw @flamber suggest posting a stacktrace. I'm sorry. I'm convused. I don't see Admin > Troubleshooting > Logs. I see a gear in the lower left of the home page with a choice for Admin Settings,. That only gives me these menu items:
Hi @tbc
Someone has created a nested question (a question using another Saved Question as it's base), and you don't have access to the nested question.
But given that you are an admin, then that shouldn't be possible.
The Troubleshooting menu is in the top menu of the Admin panel.