HCRYPTPROV hProv;
HCRYPTKEY hSessionKey;
HCRYPTHASH hHash;

LPCSTR sKey = "WrSxnCNBpJ7Ko4[e#,7Ty)a0ykP)62Ce[.bAA;SuOf4*{nagx4s,;5!eHU!v=p3z";
int lHashPassword = strlen(sKey);

if (!CryptAcquireContext(&hProv, NULL, NULL,
    PROV_RSA_FULL, CRYPT_VERIFYCONTEXT))
  return;

if(!CryptCreateHash(hProv, CALG_SHA,  0 ,  0 , &hHash))
  return;

if(!CryptHashData(hHash, sKey, lHashPassword,  0 ))
  return;

if (!CryptDeriveKey(hProv, CALG_RC4, hHash,  128  <<  16  , &hSessionKey))
  return;

AnsiString s = "1234567890123445678901234567890123456789012345678901234567891234567890123456789012345678901234567890123456789012345678901234567890123";

char *mstring = s.c_str();
DWORD count=strlen(mstring);

if (!CryptEncrypt(hSessionKey,  0 , true,  0 , (BYTE*)mstring,
    &count, strlen(mstring)))
  return;