Yes, that's the big issue with Applets. Browser manufacturers don't like them - and for good reason based on the security issues they created for clients in the past. If the client's Browser security settings, or Java security settings are too high (or the security settings are controlled by an administrator of the network), they might not be presented with an option to install the plugin. You can find some relatively generic support options via
this thread on the Oracle site.
For example, my Mac won't allow Safari to install or run Applets without me adjusting the security settings. Usually, when I'm forced to tinker with Applets (hopefully never again once I finish this course I'm taking right now on JSP
), I end up using FireFox, because it has more granular security controls. I need to first tell FireFox I really want to run the Applet (big scary warning popup), then go through another level of Java security managed by the Java Control Panel (another big scary warning popup), which then opens the Java Control Panel under System Preferences where I must explicitly add the site to the authorized exception list.
That's a lot of hoops for a client to jump through just to present them with something that can be done better with newer more modern technologies.