SEL_E_SECPKG_NOT_FOUND error from AcquireCredentialsHandle()

Status = g_Sample_SecurityInit._SecurityFunc.AcquireCredentialsHandleA(
    NULL,                   // Name of principal
    UNISP_NAME_A,           // Name of package
    SECPKG_CRED_OUTBOUND,   // Flags indicating use
    NULL,                   // Pointer to logon ID
    &m_SchannelCred,        // Package specific data
    NULL,                   // Pointer to GetKey() func
    NULL,                   // Value to pass to GetKey()
    &m_hClientCreds,        // (out) Cred Handle
    &tsExpiry);             // (out) Lifetime (optional)