title: Inno Setup Could not call proc error?
body: <p>So I'm trying to build an installer for a source port called DXX-Rebirth. I compiled it, and when I run I get a "could not call proc" error right after the language select dialog. The error points to the function Descent. Here is my .iss file:</p>
  
  <pre><code>; Script generated by the Inno Setup Script Wizard.
  ; SEE THE DOCUMENTATION FOR DETAILS ON CREATING INNO SETUP SCRIPT FILES!
  
  #define MyAppName "DXX-Rebirth"
  #define MyAppName1 "D1X-Rebirth"
  #define MyAppName2 "D2X-Rebirth"
  #define MyAppVersion "0.57.0"
  #define MyAppURL "http://www.dxx-rebirth.com/"
  #define MyAppExeName "d1x-rebirth.exe"
  #define MyAppExeName2 "d2x-rebirth.exe"
  
  [Setup]
  ; NOTE: The value of AppId uniquely identifies this application.
  ; Do not use the same AppId value in installers for other applications.
  ; (To generate a new GUID, click Tools | Generate GUID inside the IDE.)
  AppId={{DF665ED8-D2A7-490A-805F-6677EFFBAB40}
  AppName={#MyAppName}
  AppVersion={#MyAppVersion}
  ;AppVerName={#MyAppName} {#MyAppVersion}
  AppPublisherURL={#MyAppURL}
  AppSupportURL={#MyAppURL}
  AppUpdatesURL={#MyAppURL}
  DefaultDirName={pf}\{#MyAppName}
  DefaultGroupName={#MyAppName}
  OutputBaseFilename=Setup
  Compression=lzma
  SolidCompression=yes
  
  [Languages]
  Name: "english"; MessagesFile: "compiler:Default.isl"
  Name: "german"; MessagesFile: "compiler:Languages\German.isl"
  
  [Tasks]
  Name: "desktopicon"; Description: "{cm:CreateDesktopIcon}"; GroupDescription: "{cm:AdditionalIcons}"; Flags: unchecked
  Name: "quicklaunchicon"; Description: "{cm:CreateQuickLaunchIcon}"; GroupDescription: "{cm:AdditionalIcons}"; Flags: unchecked
  
  [Types]
  Name: "install"; Description: "DXX-Rebirth"; Flags: iscustom
  
  [Components]
  Name: "d1x"; Description: "D1X"; Types: install
  Name: "d2x"; Description: "D2X"; Types: install
  
  [Files]
  ;D1X Files
  Source: "C:\Documents and Settings\Owner\Desktop\Downloads\d1x-rebirth_v0.57-win\d1x-rebirth_v0.57-win\d1x-rebirth.exe"; DestDir: "{app}\D1X-Rebirth"; Components: d1x; Flags: ignoreversion
  Source: "C:\Documents and Settings\Owner\Desktop\Downloads\d1x-rebirth_v0.57-win\d1x-rebirth_v0.57-win\*"; DestDir: "{app}\D1X-Rebirth"; Excludes: "C:\Documents and Settings\Owner\Desktop\Downloads\d1x-rebirth_v0.57-win\d1x-rebirth_v0.57-win\Missions,C:\Documents and Settings\Owner\Desktop\Downloads\d1x-rebirth_v0.57-win\d1x-rebirth_v0.57-win\Players,C:\Documents and Settings\Owner\Desktop\Downloads\d1x-rebirth_v0.57-win\d1x-rebirth_v0.57-win\Demos,C:\Documents and Settings\Owner\Desktop\Downloads\d1x-rebirth_v0.57-win\d1x-rebirth_v0.57-win\Screenchots"; Components: d1x; Flags: ignoreversion recursesubdirs createallsubdirs
  Source: "C:\Documents and Settings\Owner\Desktop\Downloads\d1x-rebirth_v0.57-win\d1x-rebirth_v0.57-win\Missions"; DestDir: "{app}\D1X-Rebirth"; Components: d1x; Flags: ignoreversion recursesubdirs createallsubdirs onlyifdoesntexist
  Source: "C:\Documents and Settings\Owner\Desktop\Downloads\d1x-rebirth_v0.57-win\d1x-rebirth_v0.57-win\Players"; DestDir: "{app}\D1X-Rebirth"; Components: d1x; Flags: ignoreversion recursesubdirs createallsubdirs onlyifdoesntexist
  Source: "C:\Documents and Settings\Owner\Desktop\Downloads\d1x-rebirth_v0.57-win\d1x-rebirth_v0.57-win\Demos"; DestDir: "{app}\D1X-Rebirth"; Components: d1x; Flags: ignoreversion recursesubdirs createallsubdirs onlyifdoesntexist
  Source: "C:\Documents and Settings\Owner\Desktop\Downloads\d1x-rebirth_v0.57-win\d1x-rebirth_v0.57-win\Screenshots"; DestDir: "{app}\D1X-Rebirth"; Components: d1x; Flags: ignoreversion recursesubdirs createallsubdirs onlyifdoesntexist
  ;D1 Main Files
  Source: "{code:Descent}\descent.hog"; DestDir: "{app}\D1X-Rebirth"; Components: "d1x"; Check: not DontInstall; Flags: external skipifsourcedoesntexist
  Source: "{code:Descent}\descent.pig"; DestDir: "{app}\D1X-Rebirth"; Components: "d1x"; Check: not DontInstall; Flags: external skipifsourcedoesntexist
  ;D1 Missions
  Source: "{code:Descent}\*.hog"; DestDir: "{app}\D1X-Rebirth\Missions"; Components: "d1x"; Check: InstallAll; Flags: external skipifsourcedoesntexist
  Source: "{code:Descent}\*.msn"; DestDir: "{app}\D1X-Rebirth\Missions"; Components: "d1x"; Check: InstallAll; Flags: external skipifsourcedoesntexist
  Source: "{code:Descent}\*.rdl"; DestDir: "{app}\D1X-Rebirth\Missions"; Components: "d1x"; Check: InstallAll; Flags: external skipifsourcedoesntexist
  Source: "{code:Descent}\Missions\*"; DestDir: "{app}\D1X-Rebirth\Missions"; Components: "d1x"; Check: InstallAll; Flags: external skipifsourcedoesntexist
  ;D1 Players
  Source: "{code:Descent}\*.eff:"; DestDir: "{app}\D1X-Rebirth\Players"; Components: "d1x"; Check: InstallAll; Flags: external skipifsourcedoesntexist
  Source: "{code:Descent}\*.plr:"; DestDir: "{app}\D1X-Rebirth\Players"; Components: "d1x"; Check: InstallAll; Flags: external skipifsourcedoesntexist
  Source: "{code:Descent}\*.plx:"; DestDir: "{app}\D1X-Rebirth\Players"; Components: "d1x"; Check: InstallAll; Flags: external skipifsourcedoesntexist
  Source: "{code:Descent}\*.ngp:"; DestDir: "{app}\D1X-Rebirth\Players"; Components: "d1x"; Check: InstallAll; Flags: external skipifsourcedoesntexist
  Source: "{code:Descent}\*.sg*:"; DestDir: "{app}\D1X-Rebirth\Players"; Components: "d1x"; Check: InstallAll; Flags: external skipifsourcedoesntexist
  Source: "{code:Descent}\*.mg*:"; DestDir: "{app}\D1X-Rebirth\Players"; Components: "d1x"; Check: InstallAll; Flags: external skipifsourcedoesntexist
  Source: "{code:Descent}\Players\*.eff:"; DestDir: "{app}\D1X-Rebirth\Players"; Components: "d1x"; Check: InstallAll; Flags: external skipifsourcedoesntexist
  Source: "{code:Descent}\Players\*.plr:"; DestDir: "{app}\D1X-Rebirth\Players"; Components: "d1x"; Check: InstallAll; Flags: external skipifsourcedoesntexist
  Source: "{code:Descent}\Players\*.plx:"; DestDir: "{app}\D1X-Rebirth\Players"; Components: "d1x"; Check: InstallAll; Flags: external skipifsourcedoesntexist
  Source: "{code:Descent}\Players\*.ngp:"; DestDir: "{app}\D1X-Rebirth\Players"; Components: "d1x"; Check: InstallAll; Flags: external skipifsourcedoesntexist
  Source: "{code:Descent}\Players\*.sg*:"; DestDir: "{app}\D1X-Rebirth\Players"; Components: "d1x"; Check: InstallAll; Flags: external skipifsourcedoesntexist
  Source: "{code:Descent}\Players\*.mg*:"; DestDir: "{app}\D1X-Rebirth\Players"; Components: "d1x"; Check: InstallAll; Flags: external skipifsourcedoesntexist
  ;D2X Files
  Source: "C:\Documents and Settings\Owner\Desktop\Downloads\d2x-rebirth_v0.57-win\d2x-rebirth_v0.57-win\d2x-rebirth.exe"; DestDir: "{app}\D2X-Rebirth"; Components: d2x; Flags: ignoreversion
  Source: "C:\Documents and Settings\Owner\Desktop\Downloads\d2x-rebirth_v0.57-win\d2x-rebirth_v0.57-win\*"; DestDir: "{app}\D2X-Rebirth"; Excludes: "C:\Documents and Settings\Owner\Desktop\Downloads\d2x-rebirth_v0.57-win\d2x-rebirth_v0.57-win\Missions,C:\Documents and Settings\Owner\Desktop\Downloads\d2x-rebirth_v0.57-win\d2x-rebirth_v0.57-win\Players,C:\Documents and Settings\Owner\Desktop\Downloads\d2x-rebirth_v0.57-win\d2x-rebirth_v0.57-win\Demos,C:\Documents and Settings\Owner\Desktop\Downloads\d2x-rebirth_v0.57-win\d2x-rebirth_v0.57-win\Screenshots"; Components: d2x; Flags: ignoreversion recursesubdirs createallsubdirs
  Source: "C:\Documents and Settings\Owner\Desktop\Downloads\d2x-rebirth_v0.57-win\d2x-rebirth_v0.57-win\Missions"; DestDir: "{app}\D2X-Rebirth"; Components: d2x; Flags: ignoreversion recursesubdirs createallsubdirs onlyifdoesntexist
  Source: "C:\Documents and Settings\Owner\Desktop\Downloads\d2x-rebirth_v0.57-win\d2x-rebirth_v0.57-win\Players"; DestDir: "{app}\D2X-Rebirth"; Components: d2x; Flags: ignoreversion recursesubdirs createallsubdirs onlyifdoesntexist
  Source: "C:\Documents and Settings\Owner\Desktop\Downloads\d2x-rebirth_v0.57-win\d2x-rebirth_v0.57-win\Demos"; DestDir: "{app}\D2X-Rebirth"; Components: d2x; Flags: ignoreversion recursesubdirs createallsubdirs onlyifdoesntexist
  Source: "C:\Documents and Settings\Owner\Desktop\Downloads\d2x-rebirth_v0.57-win\d2x-rebirth_v0.57-win\Screenshots"; DestDir: "{app}\D2X-Rebirth"; Components: d2x; Flags: ignoreversion recursesubdirs createallsubdirs onlyifdoesntexist
  ;D2 Main Files
  Source: "{code:DescentTwo}\descent2.ham"; DestDir: "{app}\D2X-Rebirth"; Components: "d2x"; Check: not DontInstall; Flags: external skipifsourcedoesntexist
  Source: "{code:DescentTwo}\descent2.hog"; DestDir: "{app}\D2X-Rebirth"; Components: "d2x"; Check: not DontInstall; Flags: external skipifsourcedoesntexist
  Source: "{code:DescentTwo}\descent2.s11"; DestDir: "{app}\D2X-Rebirth"; Components: "d2x"; Check: not DontInstall; Flags: external skipifsourcedoesntexist
  Source: "{code:DescentTwo}\descent2.s22"; DestDir: "{app}\D2X-Rebirth"; Components: "d2x"; Check: not DontInstall; Flags: external skipifsourcedoesntexist
  Source: "{code:DescentTwo}\alien1.pig"; DestDir: "{app}\D2X-Rebirth"; Components: "d2x"; Check: not DontInstall; Flags: external skipifsourcedoesntexist
  Source: "{code:DescentTwo}\alien2.pig"; DestDir: "{app}\D2X-Rebirth"; Components: "d2x"; Check: not DontInstall; Flags: external skipifsourcedoesntexist
  Source: "{code:DescentTwo}\fire.pig"; DestDir: "{app}\D2X-Rebirth"; Components: "d2x"; Check: not DontInstall; Flags: external skipifsourcedoesntexist
  Source: "{code:DescentTwo}\groupa.pig"; DestDir: "{app}\D2X-Rebirth"; Components: "d2x"; Check: not DontInstall; Flags: external skipifsourcedoesntexist
  Source: "{code:DescentTwo}\ice.pig"; DestDir: "{app}\D2X-Rebirth"; Components: "d2x"; Check: not DontInstall; Flags: external skipifsourcedoesntexist
  Source: "{code:DescentTwo}\water.pig"; DestDir: "{app}\D2X-Rebirth"; Components: "d2x"; Check: not DontInstall; Flags: external skipifsourcedoesntexist
  Source: "{code:DescentTwo}\intro-h.mvl"; DestDir: "{app}\D2X-Rebirth"; Components: "d2x"; Check: not DontInstall; Flags: external skipifsourcedoesntexist
  Source: "{code:DescentTwo}\intro-l.mvl"; DestDir: "{app}\D2X-Rebirth"; Components: "d2x"; Check: not DontInstall; Flags: external skipifsourcedoesntexist
  Source: "{code:DescentTwo}\other-h.mvl"; DestDir: "{app}\D2X-Rebirth"; Components: "d2x"; Check: not DontInstall; Flags: external skipifsourcedoesntexist
  Source: "{code:DescentTwo}\other-l.mvl"; DestDir: "{app}\D2X-Rebirth"; Components: "d2x"; Check: not DontInstall; Flags: external skipifsourcedoesntexist
  Source: "{code:DescentTwo}\robots-h.mvl"; DestDir: "{app}\D2X-Rebirth"; Components: "d2x"; Check: not DontInstall; Flags: external skipifsourcedoesntexist
  Source: "{code:DescentTwo}\robots-l.mvl"; DestDir: "{app}\D2X-Rebirth"; Components: "d2x"; Check: not DontInstall; Flags: external skipifsourcedoesntexist
  ;Vertigo
  Source: "{code:DescentTwo}\d2x-h.mvl"; DestDir: "{app}\D2X-Rebirth"; Components: "d2x"; Check: not DontInstall; Flags: external skipifsourcedoesntexist
  Source: "{code:DescentTwo}\d2x-l.mvl"; DestDir: "{app}\D2X-Rebirth"; Components: "d2x"; Check: not DontInstall; Flags: external skipifsourcedoesntexist
  Source: "{code:DescentTwo}\hoard.ham"; DestDir: "{app}\D2X-Rebirth"; Components: "d2x"; Check: not DontInstall; Flags: external skipifsourcedoesntexist
  Source: "{code:DescentTwo}\d2x.hog"; DestDir: "{app}\D2X-Rebirth\Missions"; Components: "d2x"; Check: not DontInstall; Flags: external skipifsourcedoesntexist
  Source: "{code:DescentTwo}\d2x.mn2"; DestDir: "{app}\D2X-Rebirth\Missions"; Components: "d2x"; Check: not DontInstall; Flags: external skipifsourcedoesntexist
  Source: "{code:DescentTwo}\Missions\d2x.hog"; DestDir: "{app}\D2X-Rebirth\Missions"; Components: "d2x"; Check: not DontInstall; Flags: external skipifsourcedoesntexist
  Source: "{code:DescentTwo}\Missions\d2x.mn2"; DestDir: "{app}\D2X-Rebirth\Missions"; Components: "d2x"; Check: not DontInstall; Flags: external skipifsourcedoesntexist
  ;D2 Missions
  Source: "{code:DescentTwo}\*.hog"; DestDir: "{app}\D2X-Rebirth\Missions"; Components: "d2x"; Check: InstallAll; Flags: external skipifsourcedoesntexist
  Source: "{code:DescentTwo}\*.mn2"; DestDir: "{app}\D2X-Rebirth\Missions"; Components: "d2x"; Check: InstallAll; Flags: external skipifsourcedoesntexist
  Source: "{code:DescentTwo}\Missions\*"; DestDir: "{app}\D2X-Rebirth\Missions"; Components: "d2x"; Check: InstallAll; Flags: external skipifsourcedoesntexist
  ;D2 Players
  Source: "{code:DescentTwo}\*.eff:"; DestDir: "{app}\D2X-Rebirth\Players"; Components: "d2x"; Check: InstallAll; Flags: external skipifsourcedoesntexist
  Source: "{code:DescentTwo}\*.plr:"; DestDir: "{app}\D2X-Rebirth\Players"; Components: "d2x"; Check: InstallAll; Flags: external skipifsourcedoesntexist
  Source: "{code:DescentTwo}\*.plx:"; DestDir: "{app}\D2X-Rebirth\Players"; Components: "d2x"; Check: InstallAll; Flags: external skipifsourcedoesntexist
  Source: "{code:DescentTwo}\*.ngp:"; DestDir: "{app}\D2X-Rebirth\Players"; Components: "d2x"; Check: InstallAll; Flags: external skipifsourcedoesntexist
  Source: "{code:DescentTwo}\*.sg*:"; DestDir: "{app}\D2X-Rebirth\Players"; Components: "d2x"; Check: InstallAll; Flags: external skipifsourcedoesntexist
  Source: "{code:DescentTwo}\*.mg*:"; DestDir: "{app}\D2X-Rebirth\Players"; Components: "d2x"; Check: InstallAll; Flags: external skipifsourcedoesntexist
  Source: "{code:DescentTwo}\Players\*.eff:"; DestDir: "{app}\D2X-Rebirth\Players"; Components: "d2x"; Check: InstallAll; Flags: external skipifsourcedoesntexist
  Source: "{code:DescentTwo}\Players\*.plr:"; DestDir: "{app}\D2X-Rebirth\Players"; Components: "d2x"; Check: InstallAll; Flags: external skipifsourcedoesntexist
  Source: "{code:DescentTwo}\Players\*.plx:"; DestDir: "{app}\D2X-Rebirth\Players"; Components: "d2x"; Check: InstallAll; Flags: external skipifsourcedoesntexist
  Source: "{code:DescentTwo}\Players\*.ngp:"; DestDir: "{app}\D2X-Rebirth\Players"; Components: "d2x"; Check: InstallAll; Flags: external skipifsourcedoesntexist
  Source: "{code:DescentTwo}\Players\*.sg*:"; DestDir: "{app}\D2X-Rebirth\Players"; Components: "d2x"; Check: InstallAll; Flags: external skipifsourcedoesntexist
  Source: "{code:DescentTwo}\Players\*.mg*:"; DestDir: "{app}\D2X-Rebirth\Players"; Components: "d2x"; Check: InstallAll; Flags: external skipifsourcedoesntexist
  ; NOTE: Don't use "Flags: ignoreversion" on any shared system files
  
  [Icons]
  Name: "{group}\{#MyAppName1}"; Filename: "{app}\D1X-Rebirth\{#MyAppExeName}"
  Name: "{group}\{#MyAppName2}"; Filename: "{app}\D2X-Rebirth\{#MyAppExeName2}"
  Name: "{group}\{cm:UninstallProgram,{#MyAppName}}"; Filename: "{uninstallexe}"
  Name: "{commondesktop}\{#MyAppName1}"; Filename: "{app}\D1X-Rebirth\{#MyAppExeName}"; Tasks: desktopicon
  Name: "{commondesktop}\{#MyAppName2}"; Filename: "{app}\D2X-Rebirth\{#MyAppExeName2}"; Tasks: desktopicon
  Name: "{userappdata}\Microsoft\Internet Explorer\Quick Launch\{#MyAppName1}"; Filename: "{app}\D1X-Rebirth\{#MyAppExeName}"; Tasks: quicklaunchicon
  Name: "{userappdata}\Microsoft\Internet Explorer\Quick Launch\{#MyAppName2}"; Filename: "{app}\D2X-Rebirth\{#MyAppExeName2}"; Tasks: quicklaunchicon
  
  [Run]
  Filename: "{app}\D1X-Rebirth\{#MyAppExeName}"; Description: "{cm:LaunchProgram,{#StringChange(MyAppName1, "&amp;", "&amp;&amp;")}}"; Flags: nowait postinstall skipifsilent unchecked
  Filename: "{app}\D2X-Rebirth\{#MyAppExeName2}"; Description: "{cm:LaunchProgram,{#StringChange(MyAppName2, "&amp;", "&amp;&amp;")}}"; Flags: nowait postinstall skipifsilent unchecked
  
  [Code]
  // global vars
  var
    SampleDataPage: TInputOptionWizardPage;
    DataDirPage: TInputDirWizardPage;
  
  // custom wizard page setup, for data dir.
  procedure InitializeWizard;
  begin
    { Taken from CodeDlg.iss example script }
    { Create custom pages to show during install }
  
    SampleDataPage := CreateInputOptionPage(wpSelectComponents,
      'Install Descent Data', '',
      'Would you like to copy the Descent game files to your DXX-Rebirth installation?',
      True, False);
    SampleDataPage.Add('Yes copy the game files, missions, players, and savegames.');
    SampleDataPage.Add('Yes, but just copy the game files.');
    SampleDataPage.Add('No, I'+chr(39)+'ll copy the game files myself later.');
  
    SampleDataPage.Values[0] := True;
  
    DataDirPage := CreateInputDirPage(SampleDataPage.ID,
    'Descent Data Directory', '',
    'Please select the location where the original Descent files are installed.',
    False, '');
    DataDirPage.Add('Descent location.');
    DataDirPage.Add('Decent 2 location.');
  
    DataDirPage.Values[0] := ExpandConstant('{pf}\GOG.com\Descent and Descent 2\Descent');
    DataDirPage.Values[1] := ExpandConstant('{pf}\GOG.com\Descent and Descent 2\Descent 2');
  
  end;
  
  function InstallAll(): Boolean;
  begin
    { Return the value of the 'install' radiobutton }
    //MsgBox('InstallSampleData.', mbError, MB_OK);
    Result := SampleDataPage.Values[0];
  end;
  
  function Install(): Boolean;
  begin
    { Return the value of the 'install' radiobutton }
    //MsgBox('InstallSampleData.', mbError, MB_OK);
    Result := SampleDataPage.Values[1];
  end;
  
  function DontInstall(): Boolean;
  begin
    Result := SampleDataPage.Values[2];
  end;
  
  function Descent(Param: String): String;
  begin
    { Return the selected DataDir }
    //MsgBox('GetDataDir.', mbError, MB_OK);
    Result := DataDirPage.Values[0];
  end;
  
  function DescentTwo(Param: String): string;
  begin
    { Return the selected DataDir }
    //MsgBox('GetDataDir.', mbError, MB_OK);
    Result := DataDirPage.Values[1];
  end;
  </code></pre>
  
  <p>Thanks in advance! :)</p>