Converting DirectX 9.0c to DirectX 11 Error ->Begin

Trying to Convert DirectX 9.0c into DirectX 11 Error comes out when i used ->BeginPass while using the old ->Pass there's nothing wrong.

Error: cPasses

m_pMask->Begin(&cPasses, 0);

this is the return value of the shown

HRESULT CShader::Pass(UINT nPass)
{
    HRESULT ret = m_pMask->BeginPass(nPass);
    if (ret == D3D_OK)
        ret = m_pMask->CommitChanges();
    m_pEffect->EndPass();
    return ret;
}

{
    UINT cPasses;
    m_pMask->Begin(&cPasses, 0);
    for (UINT iPass = 0; iPass < cPasses; iPass++)
    {
        Pass(iPass);
        m_pd3dDevice->DrawPrimitiveUP( D3DPT_TRIANGLESTRIP, 2, vertex, sizeof( TEXTUREVERTEX ) );
    }
    m_pMask->End();
}