Fix Adobe Acrobat Reader could not open PDF because it is either not a supported file type or because the file has been damaged error on PC.

Microsoft has released an optional out-of-band update for all supported Windows 10 versions to address an issue preventing customers from opening PDF documents using some applications.

If you have a confidential PDF you want to password protect, you have a few ways to do that on your Windows 11 PC. You can use a desktop app or a web-based tool to encrypt your PDF files.