[cityguy]

Firefox plugin starts new instance of JD each time a selection of links is added from a webpage. Does not seem to realize that it's already running.

You have to disable your Firewall for JDownloader (give permissions to newest javaw.exe in your Program Files/Java Directory)

[cityguy]

I don't understand. JD is downloading fine. But when I use the Firefox plugin to "Download Selected Links" it starts a new instance of JD. So I now have two icons in the notification area. Maximizing either shows the entire list of downloads. Selecting yet another set of links by right-clicking on a web page link will start yet another instance of JD and adds another new icon to the notification area. And this will continue ad naseum. It's adding the links fine but should not be starting a new occurrence of JD.

JD starts a local TCP Server to communicate with instances. If your Firewall is blocking the communication (which is your problem), every new instance thinks there is no other...

This has nothing to do with the ability to download..

[cityguy]

I checked my firewall java.exe was listed already. I've added javaw.exe. I really don't understand why but it does seem to have solved my issue but why wouldn't I get a prompt from the firewall asking for access for javaw.exe?

Thanks for you're help.

[Jiaz]

You can visit support chat (better ask for a time here, because i will not have much time this weekend) and then i can help you live with teamviewer.
you need to setup 3 excludes: java.exe , javaw.exe and jdownloader.exe and be sure you did not install several java version. better deinstall all java and install the latest again.