No plugin connection in windows 8

I'm under a domain, client windows 8.0 e 8.1.
I install the plugin as administrator user; when I enter as a normal user, I get the "no plugin...", I can reinstall it (with admin rights) but next time I'll get the same error. Why?
I'm in a school environment, with lots of different users...
Regards.

School and corporate environments may on occasion require more than just administrator rights.

There are at least two levels of "Administrator" and in such cases you will either have to talk to your IT department or be granted FULL admin rights.

Differing scenarios can call for different approaches to this issue.
You may also be able to use the "RUN AS ADMINISTRATOR" option if it is available to you.

Bob.