You have installed a very old version of Ubuntu, released in April 2008.
Where there are problems, such as yours in refusing to shut down, they are
generally fixed in the next revision. Unless there is some very unusual
reason not to use the current release (12.04 ) you should as it will give
you better results. It is a long term release and supported for 5 years.
The price is the same: free to download, burn to CD and use.

There is a VERY good reason for his installation as EMC2 uses a RT
kernel for powering his CNC machine. To my knowledge, LinuxCNC has
not developed an update to 12.04

Not all that familiar with linux kernels etc? But
after posting and from the input I'm not realizing there is a difference.

There is an updated version for Ubuntu 8.04 with EMC2 kernel that I am now
downloading, 10.04.3 LTS if that makes any sense. I'm hoping that as Leslie
posted that this latest version will have taken that matter into consideration?

Essentially Art, you have discovered what I left out. I want to install the
Ubuntu with the EMC2 on one of the hard drives to see if I can get my cnc that
uses EMC2 to power the machine. Hardy Heron is fine, except you can't power it
down. Not a big deal but I would consider it a basic requirement.

The Windows XP, I'm hoping that maybe eventually I can download Mach 3 which is
windows oriented for cnc machines that use Mach 3 with windows. If that makes
sense?? First cnc adventure as a newby & linux beginner, so I have a long way to
go.

Appreciate all the help with this matter that was posted. If the update does not
have error taken care of ........

I'm not at all aware of the details of your special needs that require you
to use 8.04. Sorry if I confused things for you!

I can, however, offer a workaround that will allow you to shut down Ubuntu
safely. Press and hold Alt and SysReq (may have a slightly different
spelling on some keyboards). Then press in order, waiting until all disk
activity has stopped (a few second) between each, R E I S U B. This closes
all open files and does an orderly and safe shutdown. You will never lose
any data shutting down this way. Just powering off is probably 99% safe but
this is 100% safe.

That's a good idea, the R E I S U B shut down sequence. Can I add a
couple of tweaks?

First, you need to keep the ALT key held down all the way through the
sequence, from PrtScrn on.

Second, the B stands for Boot, i.e. reboot, so for a shutdown make it O
instead: Alt-PrtScrn, Alt-R, Alt-E, Alt-I, Alt-S, Alt-U, Alt-O


I also endorse the idea of moving on from Hardy, because it's no longer
supported by the makers (having moved on). I 'm not au fait with EMC2 or
CNC either, but I see they need a specialised real-time kernel.

Hopefully the 10.04 (Lucid Lynx) LTS release that you have found will
solve the shutdown problem and include what you need. But even that will
reach the end of its support life in 9 months time: up until now Ubuntu
LTS releases have had a support period of three years (five for server
editions). Non- LTS releases (LTS = Long Term Support) are only
supported for 18 months.

But Ubuntu 12.04 (Precise Pangolin) LTS is for the first time to be
supported for five years in its desktop editions, so /if/ an upgrade
with a real-time kernel exists that would be a much better bet.
This page suggests that a real-time patch for 12.04 is now available:
askubuntu.com/.../how-can-i-install-a-realtime-kernel, but
you'll probably want to do some further research to make sure it will
meet your needs.

There is another reason that 12.04 may be unpalatable: the need to learn
a new user interface. However all the advice is that we're all (even
Windows users!) going to have to swallow the change from desktop to
launcher sooner or later so it's worth biting that bullet.