Comment 42 for bug 197589

I have two desktop computers. Both upgrades from 7.10 to 8.04 were painful. Normal internet upgrade failed during the install process and cd-upgrade's automatic option didn't work either.
"A dialog will be displayed offering you the opportunity to upgrade using that CD. "
- Ubuntu

"If the upgrade dialog is not displayed for any reason, you may also run the following command using Alt+F2: "
Not so straight work flow even here. A message popped up claiming that cd is not mounted, which it surely was. After remounting system seemed to hang but the announcement was hidden. It was under all the other windows but nothing indicated that it even exists.

Next step was to realize that cd-upgrade is defenately not going to do anything nor it is giving any instructions. The lacking piece of advise was that cd should be added to one's download sources. After that and number of error pop-ups everything seemed to be ok, but my numpad stopped responding. As I mentioned, all this happened during both hardy upgrades.

Solution (which is surely not intuitive) was this already mentioned one:
" 1. Go to System > Preferences > Accessibility > Keyboard Accessibility
   2. Select [x] Enable keyboard accessibility features
   3. Go to the tab Mouse Keys and deselect [ ] Enable keyboard accessibility features."

- Ubuntu - rather stable if not upgraded to LTS.