serious problem with directx installation

HI,

MY problem ist that the installation of directx at the end of the pmdg777 installation fails. It says a cabinet file necessary for installation cannot be trusted. Please verify the cryptographic services are enabled and the cabinet file certificate is valid.

This ends up in the problem that the 777 does not work. No gauges are installed and no activation window.

I had the same problem with the 737NGX but i don't know how i fixed it that time.

I seached the internet for the problem and downloaded the dirext webinstaller which gives the same problem. Also the complete installer from JUn2010 gives the same problem.

The cryptographic services are enabled anyway but it doenst work, always the same failure.

What is the solution? Did anyone experience the same?

Thanks

Chris Thiel