Exception "Unable to insert a line" TComboBox with CharCase ecLowerCase or ecUpperCase

Question

In Delphi 10.3.2, when I programmatically insert items in a TComboBox having "CharCase = ecLowerCase" (or ecUpperCase), I get the error Project XXXX raise exception class EOutOfResources with message 'Unable to insert a line'

The error only appears when I add to my project the unit SHAREMEM (I need to reference that unit as I have to exchange dynamic strings with a DLL).

It seems that the error is related to this remark I found in the procedure TComboBoxStrings.Add() (unit StdCtrls.pas): From the Windows SDK documentation: Comclt32.dll version 5.0 or later: If CBS_LOWERCASE or CBS_UPPERCASE is set, the Unicode version of CB_ADDSTRING alters the string. If using read-only global memory, this causes the application to fail.

program combo_lowercase;

uses ShareMem,
  Vcl.Forms,
  Unit1 in 'Unit1.pas' {Form1};

{$R *.res}

begin
  Application.Initialize;
  Application.MainFormOnTaskbar := True;
  Application.CreateForm(TForm1, Form1);
  Application.Run;
end.

---

unit Unit1;

interface

uses Forms, Winapi.Windows, Winapi.Messages, System.SysUtils, System.Variants, System.Classes, Vcl.Controls, Vcl.StdCtrls;

type
  TForm1 = class(TForm)
     combo: TComboBox;
     procedure FormCreate(Sender: TObject);
  end;

var Form1: TForm1;

implementation

{$R *.dfm}

procedure TForm1.FormCreate(Sender: TObject);
begin
    combo.Items.Clear;
    combo.Items.Add('AAAAAAAAAAAAAA');
    combo.Items.Add('bbbbbbbbbbbbbb');
    combo.Items.Add('CCCCCccccccccc');
    combo.Items.Add('ddddddDDDDDDDD');
end;

end.

---

object Form1: TForm1
  Left = 0
  Top = 0
  Caption = 'Form1'
  ClientHeight = 206
  ClientWidth = 496
  Color = clBtnFace
  Font.Charset = DEFAULT_CHARSET
  Font.Color = clWindowText
  Font.Height = -11
  Font.Name = 'Tahoma'
  Font.Style = []
  OldCreateOrder = False
  OnCreate = FormCreate
  PixelsPerInch = 96
  TextHeight = 13
  object combo: TComboBox
     Left = 48
     Top = 20
     Width = 145
     Height = 21
     Style = csDropDownList
     CharCase = ecLowerCase
     TabOrder = 0
  end
end

Is there a workaround? Thanks in advance.

Answer 1

The code you show does not lead to the error that you report. The only explanation I can come up with to account for the significance of Sharemem is that its use leads to an erroneous version of borlandmm.dll being loaded. Make sure that your process loads the correct version of that DLL. Copy it from the bin directory to the same directory as your executable.