如何从Inno Setup安装JRE？

我正在尝试通过Inno Setup（以及其他应用程序）安装最新的平台（x64或x86）合适的Java Runtime Environment。我找到了一些脚本示例，这些脚本示例说明了如何检测版本并在正确的情况下进行安装并使其适应我的需要，但我一直遇到以下问题：

无法打开文件“ path \ to \ JREInstall.exe”：
CreateProcess失败：代码5：
拒绝访问

这是严格负责安装JRE的代码：

[Setup]
AppName="JRE Setup"
AppVersion=0.1
DefaultDirName="JRE Setup"

[Languages]
Name: "english"; MessagesFile: "compiler:Default.isl"

[Files]
Source: "jre-8u11-windows-x64.exe"; DestDir: "{tmp}\JREInstall.exe"; \
    Check: IsWin64 AND InstallJava();
Source: "jre-8u11-windows-i586.exe"; DestDir: "{tmp}\JREInstall.exe"; \
    Check: (NOT IsWin64) AND InstallJava();

[Run]
Filename: "{tmp}\JREInstall.exe"; Parameters: "/s"; \
    Flags: nowait postinstall runhidden runascurrentuser; Check: InstallJava()

[Code]

procedure DecodeVersion(verstr: String; var verint: array of Integer);
var
  i,p: Integer; s: string;
begin
  { initialize array }
  verint := [0,0,0,0];
  i := 0;
  while ((Length(verstr) > 0) and (i < 4)) do
  begin
    p := pos ('.', verstr);
    if p > 0 then
    begin
      if p = 1 then s:= '0' else s:= Copy (verstr, 1, p - 1);
      verint[i] := StrToInt(s);
      i := i + 1;
      verstr := Copy (verstr, p+1, Length(verstr));
    end
    else
    begin
      verint[i] := StrToInt (verstr);
      verstr := '';
    end;
  end;
end;

function CompareVersion (ver1, ver2: String) : Integer;
var
  verint1, verint2: array of Integer;
  i: integer;
begin
  SetArrayLength (verint1, 4);
  DecodeVersion (ver1, verint1);

  SetArrayLength (verint2, 4);
  DecodeVersion (ver2, verint2);

  Result := 0; i := 0;
  while ((Result = 0) and ( i < 4 )) do
  begin
    if verint1[i] > verint2[i] then
      Result := 1
    else
      if verint1[i] < verint2[i] then
        Result := -1
      else
        Result := 0;
    i := i + 1;
  end;
end;

function InstallJava() : Boolean;
var
  ErrCode: Integer;
  JVer: String;
  InstallJ: Boolean;
begin
  RegQueryStringValue(
    HKLM, 'SOFTWARE\JavaSoft\Java Runtime Environment', 'CurrentVersion', JVer);
  InstallJ := true;
  if Length( JVer ) > 0 then
  begin
    if CompareVersion(JVer, '1.8') >= 0 then
    begin
      InstallJ := false;
    end;
  end;
  Result := InstallJ;
end;

在完整的安装脚本中，相同的消息继续出现。如何从该脚本化安装文件中运行JRE安装程序？