duplicated f14 in prep for preupgrade to f16, can't login

[jackson byers]

In preparation for trying preupgrade from my existing f14,
I duplicated the f14 on another partition.

This copy of f14 boots, boot messages all OK.

But I can't login to it,
 either in the graphical login window
or going to text screen.
Both just endlessly recycle me back to the login.

I don't want to use the original f14 to preupgrade;
in case of preupgrade failure,
 I could be stuck with no f16 and a damaged f14

thanks for
any hints,
advice.

Jack