$uninst=ReadValue("HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Uninstall\Adobe Acrobat 7.0","UninstallString")
If $uninst<>""
If Exist ("C:\Program Files\Adobe\Acrobat 7.0\Acrobat\Acrobat.exe") Exit EndIf

$uninst=ReadValue("HKLM\SOFTWARE\Microsoft\Windows\CurrentVersion\Uninstall\Adobe Acrobat 7.0","UninstallString")
If $uninst <> ""
     If Exist("C:\Program Files\Adobe\Acrobat 7.0\Acrobat\Acrobat.exe")
          <here is where you'd perform the uninstall>
     EndIf
EndIf

Break on

$key = "HKLM\SOFTWARE\Microsoft\Windows\CurrentVersion\Uninstall\"

$ar6 = ReadValue($key + "Adobe Acrobat 6.0","UninstallString")
$ar7 = ReadValue($key + "Adobe Acrobat 7.0","UninstallString")
$ar8 = Exist("C:\Program Files\Adobe\Reader 8.0\Reader\AcroRd32.exe")
;
If $ar6 <> ""
	;Acrobat 6 detected, uninstall. Parse string, add '-y' For quiet mode
	$leftpart=Left($uninst,InStr($uninst,"-f")-2)
	$rightpart=Right($uninst,Len($uninst)-InStr($uninst,"-f")+1)
	$uninst=$leftpart+" -y -a -x "+$rightpart
	Shell $uninst
EndIf
If $ar7 <> ""
	; Acrobat 7 detected, uninstall. Parse string, add '-y' for quiet mode
	$leftpart=Left($uninst,InStr($uninst,"-f")-2)
	$rightpart=Right($uninst,Len($uninst)-InStr($uninst,"-f")+1)
	$uninst=$leftpart+" -y -a -x "+$rightpart
	Shell $uninst
EndIf
If $ar8 <> "1"
	MessageBox("Installing Adobe Reader 8.0","ESI International",,2)
	Shell '%systemroot%\system32\msiexec.exe /qb!- /i"\\william\admin\users\adobereader\8\AdobeReader 8.0.msi"'
	WriteValue ("HKLM\SOFTWARE\Adobe\Acrobat Reader\8.0\AdobeViewer\", "EULA", "1", "REG_DWord")
EndIf