Problem with win10 opening downloaded pdf

[AAPAPA]

When trying to open some pdf files downloaded from internet sites I get the message

Quote

Adobe Acrobat

Adobe Acrobat Reader could not open 'c06208876.pdf because it is either not a supported file type or because the file has been damaged (for example, it was sent as an email attachment and wasn't correctly decoded).

Foe Example see

https://support.hp.com/us-en/product/hp-255-g7-notebook-pc/24381324/model/24381328/manuals Maintenance Manual

[Bernd Alheit]

Download the file to the local disc and open it in Acrobat Reader.

[try67]

Works fine for me (see attached), although my browser (Firefox) warns that the download link is not secure, so you have to tell it to download the file anyway for it to work. Otherwise it downloads as a zero-byte file, which of course can't be opened.