No voxatc window showing in FSX SE

Hi all,

I have both P3D V2.5 and FSX SE and I bought voxatc recently and installed for both system. However, I discovered that the voxatc window cannot be showing in FSX SE. Even I cannot press the 'ENABLE' button. It was flashed out for a second. On the other hand, I can use voxatc in P3D without any problem. I m using PMDG 777. Any idea that can help? Thanks a lot.