Hope you are doing well and sorry for the trouble. A described you are not able to open the PDF file.
- What is the version of the Adobe Acrobat Reader DC you are using. To check the version of the application go to Help > About Acrobat and make sure you have the latest version installed. Go to Help > Check for Updates.
- Is this a behavior with a particular PDF file or with all the PDFs? Please try with a different PDF file and check. If the file is stored on a shared network/drive please download it to your computer first and then try to open it and check.
- What happens when you try to open the PDF file, do you get any error message? If yes please share the screenshot of the same for a better understanding.