Lene 

The unwanted text are comments.

In your Project Settings, you can do uncheck Comments to not extract these segments:

Alternatevely, you can filter these segments, lock them, or something like this, and then remove the filter to start translating. To do so, in Advanced Filter Display, go to the Document Structure tab and select the Comment row (you may see C+ instead), and plress Apply Filter:

Thanks! As it turns out, the comments box was already unchecked. These are obviously comments on the document that were hidden, so I still don't know how to keep it out of the work file. It also made it impossible to do a spell check or verify because of all that extra text. Obviously document notes that weren't visible in the PPT. I'll try the other solution.

 Lene 

I know how to hide or show comments in PowerPoint, but I wouldn’t know how to hide a partiular comment. Are you sure about that?

If you open the PowerPoint presentation, do you see the comments? If so, and you client agrees, you can delete them in PowerPoint...