uses
 Registry;
procedure ReadREG_MULTI_SZ(const CurrentKey: HKey; const Subkey, ValueName: string;
 Strings: TStrings);
var
 valueType: DWORD;
 valueLen: DWORD;
 p, buffer: PChar;
 key: HKEY;
begin
 // Clear TStrings
 Strings.Clear;
 // open the specified key
 if RegOpenKeyEx(CurrentKey,
  PChar(Subkey),
  0, KEY_READ, key) = ERROR_SUCCESS then
 begin
  // retrieve the type and data for a specified value name
  SetLastError(RegQueryValueEx(key,
  PChar(ValueName),
  nil,
  @valueType,
  nil,
  @valueLen));
  if GetLastError = ERROR_SUCCESS then
  if valueType = REG_MULTI_SZ then
  begin
  GetMem(buffer, valueLen);
  try
  // receive the value's data (in an array).
  RegQueryValueEx(key,
  PChar(ValueName),
  nil,
  nil,
  PBYTE(buffer),
  @valueLen);
  // Add values to stringlist
  p := buffer;
  while p^ <> #0 do
  begin
  Strings.Add(p);
  Inc(p, lstrlen(p) + 1)
  end
  finally
  FreeMem(buffer)
  end
  end
  else
  raise ERegistryException.Create('Stringlist expected/ String Liste erwartet...')
  else
  raise ERegistryException.Create('Cannot Read MULTI_SZ Value/'+
  'Kann den MULTI_SZ Wert nicht lesen...');
 end;
end;
// Test it:
procedure TForm1.Button1Click(Sender: TObject);
begin
 ReadREG_MULTI_SZ(HKEY_CURRENT_USER, 'Software\XYZ', 'Test44', Memo1.Lines);
end;

{******************************************}
{2. by Ralph Friedman }
{
 Question:
 I want to read out the binary-value "problems" of the path
 HKEY_DYN_DATA\Config Manager\Enum\[add the key of a hardware component] to
 detect if a hardware component is troubled and not working right.
 But I cannot handle the ReadBinaryData-Method of TRegistry correct.
 Everytime I use it, it always returns "4" as content of the buffer.
 How do I detect if the content of the binary-key "problems" is
 not "00 00 00 00" but something else like "16 00 00 00" or such?
}
{Answer: Here's an example of ReadBinaryData }

procedure TFrmReadBinary.Button1Click(Sender: TObject);
const
 CKeyName: string = 'System\Setup';
 CValName: string = 'NetcardDlls';
var
 keyGood: boolean;
 p: integer;
 regKey: TRegistry;
 tmpStr: string;
 vSize: integer;
begin
 regKey := TRegistry.Create;
 try
  regKey.RootKey := HKEY_LOCAL_MACHINE;
  keyGood := regKey.OpenKey(CKeyName, False);
  if (keyGood) then
  begin
  vSize := regKey.GetDataSize(CValName);
  if (vSize > 0) then
  begin
  SetLength(tmpStr, vSize);
  regKey.ReadBinaryData(CValName, tmpstr[1], vSize);
  repeat
  p := Pos(#0, tmpStr);
  if p <> 0 then
  begin
  Delete(tmpStr, p, 1);
  Insert(#13#10, tmpStr, p);
  end;
  until p = 0;
  (*StringReplace(tmpStr, #0, #13#10, [rfReplaceAll]); *)
  ListBox1.Items.Text := tmpStr;
  end;
  end;
 finally
  regKey.Free;
 end;
end;

{******************************************}
{3. by Michael Winter }
procedure RaiseWin32Error(Code: Cardinal);
var
 Error: EWin32Error;
begin
 Error := EWin32Error.CreateResFmt(@SWin32Error, [Code,
  SysErrorMessage(Code)]);
 Error.ErrorCode := Code;
 raise Error;
end;
// Write REG_MULTI_SZ
procedure TForm1.Button1Click(Sender: TObject);
const
 Str = 'multiple'#0'strings'#0'in one'#0'registry'#0'value'#0;
var
 Reg: TRegistry;
 Res: Integer;
begin
 Reg := TRegistry.Create;
 try
  Reg.RootKey := HKEY_CURRENT_USER;
  if not Reg.OpenKey('\Software\Test\RegMultiSzTest', true) then
  raise Exception.Create('Can''t open key');
  Res := RegSetValueEx(
  Reg.CurrentKey, // handle of key to set value for
  'TestValue', // address of value to set
  0, // reserved
  REG_MULTI_SZ, // flag for value type
  PChar(Str), // address of value data
  Length(Str) + 1); // size of value data
  if Res <> ERROR_SUCCESS then
  RaiseWin32Error(Res);
 finally
  Reg.Free;
 end;
end;
// Read REG_MULTI_SZ
procedure TForm1.Button2Click(Sender: TObject);
var
 Reg: TRegistry;
 DataType: Cardinal;
 DataSize: Cardinal;
 Res: Integer;
 Str: String;
 i: Integer;
begin
 Reg := TRegistry.Create;
 try
  Reg.RootKey := HKEY_CURRENT_USER;
  if not Reg.OpenKeyReadOnly('\Software\Test\RegMultiSzTest') then
  raise Exception.Create('Can''t open key');
  DataSize := 0;
  Res := RegQueryValueEx(
  Reg.CurrentKey, // handle of key to query
  'TestValue', // address of name of value to query
  nil, // reserved
  @DataType, // address of buffer for value type
  nil, // address of data buffer
  @DataSize); // address of data buffer size
  if Res <> ERROR_SUCCESS then
  RaiseWin32Error(Res);
  if DataType <> REG_MULTI_SZ then
  raise Exception.Create('Wrong data type');
  SetLength(Str, DataSize - 1);
  if DataSize > 1 then begin
  Res := RegQueryValueEx(
  Reg.CurrentKey, // handle of key to query
  'TestValue', // address of name of value to query
  nil, // reserved
  @DataType, // address of buffer for value type
  PByte(Str), // address of data buffer
  @DataSize); // address of data buffer size
  if Res <> ERROR_SUCCESS then
  RaiseWin32Error(Res);
  end;
  for i := Length(Str) downto 1 do
  if Str[i] = #0 then
  Str[i] := #13;
  ShowMessage(Str);
 finally
  Reg.Free;
 end;
end;

type

{©Drkb v.3(2007): www.drkb.ru}

 TExRegistry = class(TRegistry)

 public

  function ReadStrings(const ValueName: String): String;

 end;

function TExRegistry.ReadStrings(const ValueName: String): String;

var

 ValueType : DWORD;

 ValueLen : DWORD;

 P, Buffer : PChar;

begin

 Result := '';

 SetLastError(RegQueryValueEx(CurrentKey, PChar (ValueName), nil,

  @ValueType, nil, @ValueLen));

 if GetLastError = ERROR_SUCCESS then

 begin

  if ValueType = REG_MULTI_SZ then

  begin

  GetMem(Buffer, ValueLen);

  try

  RegQueryValueEx(CurrentKey, PChar(ValueName), nil, nil, PBYTE(Buffer), @ValueLen);

  P := Buffer;

  while P^ <> #0 do

  begin

  if Result <> '' then

  Result := Result + sLineBreak;

  Result := Result + P;

  Inc(P, lstrlen(P) + 1);

  end;

  finally

  FreeMem (Buffer);

  end;

  end

  else

  raise ERegistryException.Create ('String list expected');

 end

 else

  raise Exception.Create ('Unable read MULTI_SZ value');

end;