I copied the package folder (ProPac, http://www.pages.drexel.edu/~hgk22/software/ProPac/ProPac.html) in $UserBaseDirectory/Applications
in Linux mint.
But when I called it by
<<ProPac`
the ouput is
Get::noopen: Cannot open ProPac`. >>
$Failed
I tried install it from File menu but appears the same error.
But in Windows OS I have no problem with installation of this package and using it.