Here are my notes on how to swap out icons that I had to write and repeat for myself instead of getting parts of the instructions over a few threads and a few months-worth of posts. I've used the notes a couple of times and have never had another problem swapping out icons:

HOW TO CHANGE THE TASK NAVIGATOR ICONS

**This installation assumes you have a rooting application like 'becomeroot' already installed**

1. Open up a blank web page and enter the following:

file:///usr/share/icons/hicolor/scalable/hildon/

2. Scroll to find the name of the icon you want to replace. If you want to alter the actual icon image itself, hold down the pointer, the image will open in another page, 'Save as…' and save it to a convenient folder (I've only ever saved it to my Removable Memory Card. I don't know if it'll work as well anywhere else).

3. Transfer the saved image in the convenient folder over to your desktop. Once, on the desktop, make a copy as back-up (i.e. 'xxxx.png - original').

4. Open up GIMP/PhotoShop/etc. and either create your own icon within a 48x48 pixel box (or find an icon online and reduce it to 48x48 in GIMP/PhotoShop) or open the icon image file with the unaltered file name and start altering.

5. When you're satisfied, save the image icon file - always with the same file name as the original icon image. DO NOT add '.png' at the end of the file name. For some strange reason, if the '.png' stays at the end at this step, when it gets back over to the Removable Memory card, the N800 is reading it essentially as 'xxxx.png.png' and that means it's no longer the same file name that is required to replace the original icon image file in the system.

6. Transfer the new icon image file over to the N800 and put it on the Removable Memory card.

7. Open File Manager and see if the icon image file is on the Removable Memory card. If '.png' appears in the file name, simply go up to the menu -> File -> Rename… and remove the '.png' from the file name.

8. Close File Manager

9. Open X Terminal

10. After the '~$', type the following:

sudo gainroot

11. 'Root shell enabled' should pop up

12. Using the 'personal-menu.png' icon as an example, just follow the subsequent commands as shown below. The entire thing, from step #10 onwards, is shown as it appears on the screen.

Caveat: unless there is a blank line between the commands below, assume it's because the long command is not appearing all on one line and there should be one blank space between the end of the first line and the continuation on the second line SO THAT THE LONG COMMAND LINE IS ALL ON A SINGLE LINE

13. The final command (the 'gtk-update-…') may take up to 30 seconds to produce the 'Cache file created successfully' message. Be patient

14. Once that message appears, simply reboot the N800.

15. Voila! The new icon should appear!


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BusyBox v1.6.1 (2007-09-27 18:08:59 EEST) Built-in shell (ash)
Enter 'help' for a list of built-in commands.

~ $ sudo gainroot

Root shell enabled

BusyBox v1.6.1 (2007-09-27 18:08:59 EEST) Built-in shell (ash)
Enter 'help' for a list of built-in commands.

/home/user # cd /usr/share/icons/hicolor/scalable/hildon

/usr/share/icons/hicolor/scalable/hildon # rm personal-menu.png

/usr/share/icons/hicolor/scalable/hildon # cd /media/mmc1

/media/mmc1 # cp personal-menu.png /usr/share/icons/hicolor/scalable/hildon

/media/mmc1 # cd /home/user

/home/user # gtk-update-icon-cache -f -t /usr/share/icons/hicolor

Cache file created successfully.

/home/user #


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I've never had anyone else use the notes, though. If they don't work for you, sorry .