Can't open PDF in Reader after saving to desktop, says it's an InDesign file

[prepress1p80536402]

My boss only has Reader. When anyone sends him PDFs he can open them right out of the email. But when he saves them to his desktop or files them away and then tries to open them again, he gets an error opening saying something about the indd is not supported. Strange because he does not even have the suite on his computer and after it's a PDF anyways he shouldn't have to worry about needing InDesign. It says we are opening an InDesign file but they are actually PDFs and shows a PDF icon. Is there a setting we are missing? I have never heard of this before. Thanks.

[Tariq Ahmad Dar]

Hi @prepress1p80536402, 

Thank you for reaching out with your question. 

Analyzing the screenshot and looking at the message, it seems your boss is not opening .PDF file, it is .indd

I am assuming that Reader on his machine may be the associated app for InDesign files. Please check the file extension again before opening it in Reader.
Let us know if you have further questions. 

~Tariq

[prepress1p80536402]

Thanks for responding. But I am there trying to help him but that is part of the error. It is not an InDesign file at all. It is a PDF. I don't know why it is saying that. it isn't one. It is a PDF I have sent to him before. It happens with all of his desktop files. And again, he opens them in his email directly and they open fine. It is only after they are saved to the desktop.