Thank you very much, @gerhard! 
When I try to open them, I‘m getting the message: The site ist not existing or private. And nearly everyone has <p>...</p> in common. That‘s intressting, cause I‘ve never put html code into these posts.
What is the best option:
- Can I recover / repair them? It seems the content is still available.
- If not, how can I delete them manually / automatically?
Some example:
Thank you in advance!