I am trying to install the printer driver for an HP DesignJet 500ps on a Mac running Mac OSX 10.8.5 (Mountain Lion). The drivers seem to install but the HP Printer Setup Assistant.app will not run. The error message is:
"HP printer setup assistant.app can't be opened. You should Eject disk image"
I have redownloaded the software on multiple Macs running 10.8.5 and the error comes up each time. I've also copied the Setup Assistant app to my hard drive and it won't run from there either.
Help?