When I try to open a pdf document, nothing happens. I have uninstalled and reinstalled Adobe several times. Once re-installed, it will only work for a short period of time and then I will have the problem again. I click on the pdf document to open it and nothing happens.
Since you have mentioned that, you can't open PDF file even after uninstalling and reinstalling Acrobat. You try perform couple of troubleshooting steps suggested below and see if that brings any change-
1- After reinstalling hope you have got the application installed with its latest patch version 2019.012.20035 (Win) 2019.012.20035(Mac)
2- Navigate to Reader>Edit>Preferences>Security (Enhanced)>disable "Protected Mode at Startup" and "Enhanced Security">OK>Reboot Reader