In another thread, a user with a similar error message indicated this could be caused by a specific plugin not being activated on the site: the Java Deployment Toolkit plugin (which is always set to "Ask to Activate" in Firefox).

On the site where you have this problem, check for a plugin notification icon toward the left end of the address bar (looks like a small gray Lego block, sometimes red if there is a security problem). If you click that, you can give the site temporary or ongoing permission to use any plugins the page has informed Firefox it wants to use.

Does that work?

If Firefox is not detecting the request, or if the page is very impatient, try setting the permission using the Permissions panel of the Page Info dialog. You can call that up using any of these:

• right-click a blank area of the page and choose View Page Info > Permissions
• (menu bar) Tools menu > Page Info > Permissions
• click the padlock or "i" icon to the left of the site address, then the ">" icon, then More Information > Permissions

Near the top, you'll find "Activate Plugins" and you can select Allow for the Java plugins. Then reload the page and see whether it kicks in.

Any luck?

This was very helpful information and I went through all the steps you have suggested with no success.

I continue to receive the same error with the pop up window showing disconnected.

If your IT/vendor doesn't have another suggestion, you might need to use Internet Explorer for that site.