Hello,
Can you please tell us what product you are using and which Windows version?
Also,
I'm linking the FAQ to give us the log files for investigation.
Could you also give us the exact error message?
If you use Windows 7, you need your computer up to date to verify Microsoft driver signature with Microsoft certificates. If you don't want to update your computer, then you will have to install 7.9M3 and not 7.9M4.
The icon doesn't show if there's no screen being driven.
The logs will bring a bit of clarity.
Regards,
Alban