The OzOS implementation of the Enlightenment Desktop allows an infinite number of user configuration tweaks to change the way your desktop looks and works. We are still documenting many of these in our series of OzOS Configuration How-Tos (and others emerge from time to time from the secret Mountain Eerie where the Enlightenment masters do their thing).

This How-To is a bit different - it covers the different ways you can rescue your desktop if the unthinkable happens and either you mess things up or an update does something weird and nasty to your installation or to your desktop settings.

You may want to print-out this guide or have it tattooed to an easily accessible body part so that it is available if you happen to log-on one day to an unusable desktop.

Please note: If you are new to Linux or are not comfortable using the command line, this How-To will seem a little (or very) frightening. We are sorry you feel that way. Really. As soon as we have the time we will produce a How-To on staying calm in situations of command-line-induced panic. In the meantime we can only suggest some pictures of bunnies, a good (legal) calmative or perhaps a long bath with a few drops of lavender oil. Sorry. Aubrey. (you don't have to include this bit on the tattoo)

Bad Things Happen To Good OSs

Scenarios: You get some updates but they end up unfinished with errors - or immediately (or next time you log-in) a Really Bad Thing happens. Maybe the desktop doesn't appear at all, or is unresponsive or the screen looks weird.

What to do: Don't Panic!!!

1. If the update was at fault, normal service will be resumed as soon as possible.

While you are still logged in to your dysfunctional desktop, drop to a console (eg. by using the Ctrl-Alt-F1 keys), login there and type the following command to re-install the updates:

sudo easy_e17.sh -u

That will go through the normal update process

If it still fails (maybe because the updates are still broken), there are several approaches:

You could just wait a while till the updates are fixed (and if you can still get online, you could check the OzOS forums or even the Enlightenment developers site at http://cia.vc/stats/project/e/ for relevant news)

Or you could run through the following steps to fix the problem yourself.

There are really two possible causes for a problem like this - an issue with your e17 installation or something has happened to your personal configuration files. Either way, there are tools to fix it.

2. We'll start with the possibility that your problems relate to configuration issues, rather than your e17 installation (these methods are less intrusive, so we like to try them first):

You can reapply components of the default OzOS profile with a built-in tool called oz-profiler:

oz-profiler runs from a terminal (or a console) and takes one of three "arguments":

e17-only = only restores the e17 defaults configuration (doesn't touch the users configuration to gtk stuff, bash, theme, scite...).

This is the "lightest" touch of all. You just type the following command into a terminal:

oz-profiler e17-only

Restart Enlightenment.

No luck? Ok, take it to the next level with:

oz-profiler skip-e17

This one should still preserve your desktop settings, but you may have to tweak a few things to get them back the way you like them.

Still no luck? OK, try:

oz-profiler all

And if that does not fix it, we probably have a problem with the e17 installation (rather than just the configuration). No need to panic.

3. The best way to restore a broken installation is by doing it from a backup.

Yes, you do have a backup! Each time you update e17, a backup of your existing installation is made automatically. (You can also do this easily and deliberately with the the oz-extras tool described in Section 2 below, but let's get this problem fixed first).

Restoring a backup needs to be done from outside of e17 - you actually have to have to be logged out. To enter commands without a desktop running, you will use a "console" and log in to a bare command line interface:

You call up a console with Ctrl+Alt+F1 and login at the prompt. Then type this command:

sudo update_e17.sh --replace

(Note: If you get an error saying "command not found", that simply means you don't, for some reason, have the oz-e17-tools package installed. This is easily resolved by typing "sudo apt-get install oz-e17-tools" and, when the installation is finished, re-entering the above command)

The command will list available backups.

Choose the latest.

That will reinstall a "good" e17 with all your configuration files.

(If, for some reason, you suspect you may have backed up a faulty installation, just select an even earlier backup)

If All that Fails ?

4. There are more options (of course!)

At this stage, we need to get an "old" update from the repositories. This command by-passes the latest update (which we assume is broken) and gets a previous one.

sudo update_e17.sh --date 200x-mm-dd

(the date format is flexible but year-month-day works perfectly, eg 2008-06-09. Just insert a date a few days before the update that presumably caused the problem)

Still No Joy?

If all this fails to bring back your beautiful desktop, there is still no need to panic. e17 is very flexible.

5. you can copy the e17 installation on your liveCD to your hard-drive.

Boot from the Live CD.

Mount your HD and copy the e17 files from the live session.

Example: suppose your HD partition is mounted on /media/sda1 of your LiveCD session.

Open a terminal and type:

sudo mv /media/sda1/opt/e17 /media/sda1/opt/e17_BAD
sudo cp -a /opt/e17 /media/sda1/opt/

And if that doesn't work ?

6. Well, you can panic now.

3. Bullet-proofing your OzOS installation with the OzOS Backup tool

Scenario: Having read the above, you are keen to make your own backups of your e17 installation.

What to do: Here's how to do a quick and easy e17 backup the OzOS way.

1. make sure you have oz-e17-tools installed (if not, use "sudo apt-get install oz-e17-tools" or get it via Synaptic or by using apt:foo)

2. You will know it is installed if the "Backup Enlightenment" icon is available on your Applications>System menu.

3. Use it.!

Here's the "Help" page for the tool (for use on the command line or console). (If a tattoo of this whole page is a bit much for you, you could just have this instead)

REMEMBER - The OzOS backup and restore tools only backup your e17 installation - not your other settings and files. You should maintain your own backups of these.