Even after reading all the posts, I'm still not sure what the objective is. I think that you want to first test to see if Acrobat is installed. If not then install. Then or else open it.

Checking for the existence of the file is not good practice. Also the installation can be repackaged as silent.

Here is a beta script I've got on the back burner that checks the registry to see what version of Acrobat is installed and to uninstall all but the latest version. As a beta, the action lines are commented out.

code:
break on
;Search for "Acrobat Uninstall"
$Index = 0
:Loop1
$KeyName = ENUMKEY("HKLM\SOFTWARE\Microsoft\Windows\CurrentVersion\Uninstall\", $Index)
If @ERROR = 0
  If InStr("$KeyName","Acrobat")
    "Name found: $KeyName" ?
    Select
      Case $KeyName = "Adobe Acrobat Reader 3.0"
        "Uninstall Acrobat 3.0" ?
        $UninstallStr = READVALUE("HKLM\SOFTWARE\Microsoft\Windows\CurrentVersion\Uninstall\Adobe Acrobat Reader 3.0","UninstallString")
        ;SHELL $UninstallStr + " -A"
        "Complete." ?

      Case $KeyName = "Adobe Acrobat Reader 3.01"
        "Uninstall Acrobat 3.01" ?
        $UninstallStr = READVALUE("HKLM\SOFTWARE\Microsoft\Windows\CurrentVersion\Uninstall\Adobe Acrobat Reader 3.01","UninstallString")
        ;SHELL $UninstallStr + " -A"
        "Complete." ?

      Case $KeyName = "Adobe Acrobat 4.0"
        "Uninstall Acrobat 4.0" ?
        $UninstallStr = READVALUE("HKLM\SOFTWARE\Microsoft\Windows\CurrentVersion\Uninstall\Adobe Acrobat 4.0","UninstallString")
        ;SHELL $UninstallStr + " -A"
        "Complete." ?

      Case $KeyName = "Adobe Acrobat 5.0"
        "Leave alone" ?
        Goto Done

      Case 1
        "OH OH, Not sure what to do!" ?

    EndSelect
  EndIf
  $Index = $Index + 1
  goto Loop1
EndIf

"Install Acrobat 5.05" ?
;shell 'path\setup.exe /s'

:Done

get $_
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