Hi Nick
We are sorry for the trouble. As described you are unable to open the PDFs with Adobe Acrobat DC and getting the error messgae as windows cannot find the files
Would you mind sharing the screenshot of the error message for a better understanding?
Are you getting the following error messgae 'Windows cannot find C:\Program Files (x86)\Adobe\Acrobat DC\Acrobat\Acrobat.exe' ? If yes, please try the steps below and see if that works for you.
1.Close the Adobe Acrobat DC
2. Hold down Windows key and press R on your keyboard, this will bring up Run dialogue box.
3. Type regedit in the run dialogue box and hit Enter
4. Navigate to HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows NT\CurrentVersion\Image File Execution Options, delete the key Acrobat.exe
5. Relaunch the application and check.
You may also take a look at a similar discussion https://community.adobe.com/t5/acrobat/adobe-acrobat-dc-will-not-open-a-message-comes-up-that-said-woindows-cannot-find-it/m-p/11195702?page=1#M261161
Let us know if you are referring to something else.
Regards
Amal