I Dave,
For Windows systems, you must run the standalone installer if the
computer isn't on the internet. In the fine print you will see one of
the download options is 'standalone' meaning offline install. That
file is usually 150M or greater.
At this point, I'd suggest getting the Java removal tool from Oracle
to see if it can find stray parts and make sure all of those are
removed. Sometimes a broken install can confuse the new install.
On a Windows system, parts get put in a number of different places and
things get set here and there and the installer knows all those
places.
-Ken Cameron, Member JMRI Dev Team
www.jmri.org
www.fingerlakeslivesteamers.org
www.cnymod.com
Ken Cameron