Sanity Clause wrote:

Any ideas on what may be the cause of this "Check Your Plugins"
nuisance?

Here's what I found a while back...................

http://kb.mozillazine.org/Plugin_scanning

(etc)

Preventing plugun scanning will (I think) disable the use of the plugins
in Firefox.

I could be wrong about this, but that's what I think you accomplish when
you disable plugin scanning.

Went into about:config again, changed:
plugin.scan.Acrobat from "5.0" to "9"

Closed and restarted.... ONLY MY HOME PAGE! YAAAAY!!!!!

I believe that particular change will result in Firefox NOT opening
Acrobat Reader (AR) if the installed version of AR is less than 9. So
in effect you disable AR with that setting if you have AR version 6.