My PDF Viewer in Explorer stopped working a few weeks ago. I have tried the following troubleshooting steps & they have not worked 1) Preview pane in Explorer turned on/off 2) Adobe reader "Enable PDF thumbnails previews" unchecked & re-checked. 3) uninstall/re-install Adobe reader. 4) went to Adobe program file setting & selected run in "compatibility mode" forWindow 8. 5) prayed...