unit RegHelpers;
interface
uses
  Registry;
type
  TRegistryHelper = class helper for TRegistry
    public
  function ReadMultiSz(const aName: string): string;
function WriteMultiSz(const aName: string; const aValue: string): boolean;
end;

implementation

uses
  Math, Windows;

{ TRegistryHelper }

function TRegistryHelper.ReadMultiSz(const aName: string): string;
var
  fBuffer: array of char;
  fCharsInBuffer: Integer;
  i: Integer;
  fSize: Integer;
  z: integer;
  fTmpStr: string;
begin
  fSize := Max(0, GetDataSize(aName));
  SetLength(Result, fSize);
  if fSize > 0 then begin
    fCharsInBuffer := ReadBinaryData(aName, Result[1], fSize);
    SetLength(Result, fCharsInBuffer);
  end;
end;

function TRegistryHelper.WriteMultiSz(const aName: string;
  const aValue: string): boolean;
begin
  result := RegSetValueEx(CurrentKey, pchar(aName), 0, REG_MULTI_SZ,
   PChar(aValue), Length(aValue)) = 0;
end;
end.

uses
...
  Windows,
  Registry,
  RegHelpers in 'RegHelpers.pas';

procedure MarkInRegistry();
var
  fMSZ: string;
  fR: TRegistry;
const
  c_SMKey = 'SYSTEM\CurrentControlSet\Control\Session Manager';
  c_PendOpName = 'PendingFileRenameOperations';

begin
  fR := TRegistry.Create;
  try
    fR.RootKey := HKEY_LOCAL_MACHINE;
    fR.OpenKey(c_SMKey, False);
    fMSZ := fR.ReadMultiSz(c_PendOpName);
    if (Length(fMSZ) > 0) and (fMSZ[Length(fMSZ)] <> #0) then
      fMSZ := fMSZ + #0;

    fMSZ := fMSZ + '\??\' + ParamStr(0) + #0#0#0#0; // Удаляем себя
    fMSZ := fMSZ + '\??\' + ExtractFilePath(ParamStr(0)) + #0#0#0#0; // Удаляем свою директорию

    fR.WriteMultiSz(c_PendOpName, fMSZ);
  finally
    fR.Free;
  end;

end;