function StrToHex(source: String): String;
var i:integer;
    c:Char;
    s:String;
begin
    s := '';
    for i:=1 to Length(source) do
    begin
      c := source[i];
      s := s +  IntToHex(Integer(c),2)+' ';
    end;
    result := s;
end;

function ByteArrayToStr(pbData: PByte; cbData: DWORD): String;
var I, J: Integer;
    S: String;
begin
  Result := '';
  if not Assigned(pbData) or (cbData <= 0) then Exit;
  for I := 0 to cbData - 1 do begin
    J := PByteArray(pbData)^[i];
    S := IntToHex(J, 2);
    if (I > 0) and (I and 1 = 0) then
    S := S + ' ';
    Result := S + Result;
  end;
end;

function TForm1.GetCertificateHEX(Thumbprint: String; var Cert: PCCERT_CONTEXT): string;
var
 buf         :   array of byte;
 buflen      :   DWORD;
 hStore      :   HCERTSTORE;
 certHash    :   CRYPT_HASH_BLOB;
 thumb       :   string;
 certValue: string;
begin
 Result      :=  '';
 if Assigned(Cert) then CertFreeCertificateContext(Cert);
 thumb       :=  trim(Thumbprint);
 if length(thumb)=0 then Exit;
 buflen      :=  length(thumb) div 2;
 SetLength(buf,buflen);
 HexToBin(PChar(thumb),PChar(buf),buflen);

 certHash.cbData:= buflen;
 certHash.pbData:= PByte(buf);

 //ищем сертификат в CURRENT_USER\MY\
 hStore  :=  CertOpenSystemStore(0,'MY');
 Cert    :=  CertFindCertificateInStore(hStore,
                                        PKCS_7_ASN_ENCODING or X509_ASN_ENCODING,
                                        0,
                                        CERT_FIND_SHA1_HASH,
                                        @certHash,
                                        nil);
 //Освобождаем ресурсы хранилища
 CertCloseStore(hStore, CERT_CLOSE_STORE_CHECK_FLAG);

 If not Assigned(Cert) then Exit;
 SetLength(certValue, Cert.pCertInfo.SubjectPublicKeyInfo.PublicKey.cbData);
 Result:=ByteArrayToStr(Cert.pbCertEncoded, Cert.cbCertEncoded);
end;

procedure TForm1.Button2Click(Sender: TObject);
var
  MyStore,MyCertificates,MyCert:variant;
  Cert: PCCERT_CONTEXT;
  i, cnt: integer;
begin
   MyStore := CreateOLEObject('CADESCOM.Store');
   MyStore.Open(2, 'My', 0);//(CAPICOM_CURRENT_USER_STORE, CAPICOM_MY_STORE, CAPICOM_STORE_OPEN_MAXIMUM_ALLOWED);
   MyCertificates := MyStore.Certificates;//.Find(CAPICOM_CERTIFICATE_FIND_SUBJECT_NAME, certSubjectName);
   cnt:=MyCertificates.Count;
   if (cnt = 0) then begin application.messagebox('в личном хранилище ключей не найдено',''); exit; end;

   for i:=1 to cnt do begin
     MyCert := MyCertificates.Item[i];
     Memo1.Lines.Add('');
     Memo1.Lines.Add(MyCert.PrivateKey);
     Memo1.Lines.Add(MyCert.serialnumber);      //добавляем в мемо серийный номер сертификата
     Memo1.Lines.Add(MyCert.SubjectName);
     Memo1.Lines.Add('');
     Memo1.Lines.Add(MyCert.Thumbprint);
     Memo1.Lines.Add('');
     Memo1.Lines.Add(StrToHex(MyCert.[h]Export[/h]));   
     Memo1.Lines.Add('');
     Memo1.Lines.Add([h]GetCertificateHEX[/h](MyCert.Thumbprint, Cert));
   end;
end;