Disappeared post

Hi

Today, I experienced the following while I was typing an answer to a post.

I inadvertently clicked on the image in the post, so I clicked on "Back" to get back to the text. Instead, I received this message:

So I tried to get back to the original post using the link I had from the notification email. Unfortunately, I always get the same error message.

The same happens when I do a search on the title of the post, It seems that this post has vanished! 

How is this possible? What happened here?

This is the link of the original post: The SDL Wordcount Copy installer does not work

Walter