PDF looks strange after editing text

[Computerdienst]

Hello all

My client has a strange problem when editing PDFs (source was PowerPoint).

After editing some text and saving, next time he opens the document random characters just disappeared? I attached a screen from before and after save.

Any Ideas?

Regards,

Christof

[Computerdienst]

Can't find the edit button, but I forgot: I doesn't happen always!

[JR Boulay]

You will find easier to edit the page with Powerpoint, save as PDF, then replace the page in the PDF file.