procedure TForm1.EncryptFileButtonClick(Sender: TObject);
var
  pStreamData: TMemoryStream;
  MessageArray: array of Pbyte;
  SizeArray: array of DWORD;
  SizeBuff, SizeBuf1: DWORD;
  cert : PCCERT_CONTEXT;
  hCertPubKey: HCRYPTKEY;
  phProv: HCRYPTPROV;
  addressbook: hcertstore;
begin
  pStreamData:=TMemoryStream.Create;
try
  addressbook := CertOpenSystemStore(0, 'ADDRESSBOOK');
  cert:=CertFindCertificateInStore(ADDRESSBOOK, X509_ASN_ENCODING or PKCS_7_ASN_ENCODING, 0, CERT_FIND_SUBJECT_STR, PChar(FriendCertComboBox.Text), nil);
if cert = nil then
begin
  CertFreeCertificateContext(cert);
  showmessage('Íå âûáðàí ñåðòèôèêàò');
  exit;
end;
if not CryptAcquireContext(phProv, nil, 'Crypto-Pro GOST R 34.10-2001 Cryptographic Service Provider', 75,CRYPT_VERIFYCONTEXT) then begin
  showmessage('Íå óäàëîñü ïîëó÷èòü êîíòåêñò êðèïòîïðîâàéäåðà');
  exit;
end;
if not CryptImportPublicKeyInfo(phProv,PKCS_7_ASN_ENCODING or X509_ASN_ENCODING, @cert.pCertInfo.SubjectPublicKeyInfo,hCertPubKey)
  then showmessage('Íå óäàëîñü ïîëó÷èòü êëþ÷');
  pStreamData.LoadFromFile(InputFileEdit.Text);
  SetLength(MessageArray, 1);
  SetLength(SizeArray, 1);
  MessageArray[0] := pStreamData.Memory;
  SizeArray[0] := pStreamData.Size;
if CryptEncrypt(hCertPubKey,0,true,0, nil,SizeBuff, SizeArray[0]) then
if CryptEncrypt(hCertPubKey,0,true,0, MessageArray[0],SizeBuf1, SizeBuff) then
begin
  OutputFileEdit.Text := InputFileEdit.Text+'.enc';
  pStreamData.SaveToFile(OutputFileEdit.Text);
  showmessage('Ôàéë óñïåøíî çàøèôðîâàí');
end else showmessage(SysErrorMessage(GetLastError))
  else showmessage(SysErrorMessage(GetLastError));
finally
  CertFreeCertificateContext (cert);
  pStreamData.Free;
end;
end;