Problem with CryptoAPI

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From: Seb (fiix_at_mime.univ-paris8.fr)
Date: 08/24/04 

Date: Tue, 24 Aug 2004 17:29:57 +0200

Hello,

I have read the documentation about CryptoAPI and i test the samples but
it don't work.
I would like create a key, encrypt and decrypt a file with this key.
But it's impossible to me to create a key, my source code is following:

I call Init() and after GenerateRandomKey() but CryptGetUserKey return
failed 0x8009000d
Where is the pb ?

DWORD CMsCrypto::GenerateRandomKey()
{
     if (!CryptGenKey(m_hProv, CALG_RC2, CRYPT_EXPORTABLE, &m_hKey))
     {
                CString szError;
                szError.Format(_T("Error 0x%x during CryptGenKey!\n"), GetLastError ());
                AfxMessageBox(szError);
                
                return E_FAIL;
     }
        
        // Get the handle to the key exchange public key.
        if (!CryptGetUserKey(m_hProv, AT_KEYEXCHANGE, &m_hXchgKey))
        {
                CString szError;
                szError.Format(_T("Error 0x%x during CryptGetUserKey!\n"),
GetLastError());
                AfxMessageBox(szError);
                
                return E_FAIL;
        }
        
        return NO_ERROR;
}

void CMsCrypto::Init()
{
        HCRYPTPROV hProv;
        DWORD dwFlags = CRYPT_VERIFYCONTEXT;
        
        static TCHAR *szRealProvider=TEXT("Microsoft Enhanced Cryptographic
Provider v1.0");
        static TCHAR *szWeakProvider=TEXT("Microsoft Base Cryptographic
Provider v1.0");

        if (CryptAcquireContext(&m_hProv, NULL, szRealProvider, PROV_RSA_FULL,
dwFlags)
                || (GetLastError() == NTE_BAD_KEYSET
                && CryptAcquireContext(&m_hProv, NULL, szRealProvider,
PROV_RSA_FULL,CRYPT_NEWKEYSET)
                ))
        {
                m_lpszWhichCSP = szRealProvider;
        } else {
                m_lpszWhichCSP = szWeakProvider;
        }
}

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