It is still possible to join a Lync Meeting even if you do not have the Microsoft Lync client installed on your computer.
From the meeting invitation, click on Join Lync Meeting from the meeting invitation.
This will open a website onmeet.unr.edu. You may be prompted to download a plugin. Click on Always run on this site.
Enter your name, and click on Join the meeting.
You may be prompted to install the plugin. Follow the instructions until the plugin has been successfully installed (this plugin will not harm your computer despite the warnings your browser may give). You may need to restart your browser and "Join the Meeting" again.
Click Allow to the security warning that appears. This will allow you to use the Audio/Visual and screen sharing capabilities of a Lync Meeting.
You will then enter the "Virtual Lobby" until the meeting organizer permits you to enter the meeting space.