I have an issue with installing Adobe Flash on my OSX Yosemite 10.10.4 Mac mini. Whenever I mount the dmg and run the installer I get the error: "Only a single copy of the installer can be run at a time. Please close the other window and try again."
However I cannot find this other running installer, or any other Adobe products on my computer, with Force Quit Applications, Activity Monitor, or Terminal. As far as I can tell, I have removed Flash from my computer (Application Support>Adobe, Internet Plug-Ins), uninstalled antiviruses (some threads have said that can interfere), and restarted the computer with the "Reopen windows when logging back in" unchecked, and re-downloaded the installer but the error persists.