Sorry you are having issues!
Honestly I am not sure, so this is just an idea...check the extension of the files and make sure they are still .pdf and .ppt or .doc. Sometimes when you are having issues, something could cause a change in the name of the file extension, and it will not open or if it is open, you are not able to save it (I had this happen yesterday in PowerPoint and something changed the file to a template extension .potx instead of .ppt).
After closing the application (Office or Adobe or other program), I would locate the file and check it has the right extension, and if not--change it manually. Sometimes changing the name of the file itself helps the application open it, so change the name of the file and/or extension if it is wrong and change the file name, then right click and attempt to Open With the correct program.