It is possible (though rare) for a badly implemented Replicant to make BeOS unbootable. If this happens to you, do this:

1. Put the BeOS Install CD in the drive and restart your machine*.
2. Wait for the Installer process to come all the way up, then press
   Control+Alt+Shift+T to bring up a Terminal window.

3. Type cd /boot/home/config/settings/Tracker
4. Type ls
5. You should see a file called tracker_shelf. Delete it by typing rm
   tracker_shelf

6. Type exit to close the Terminal. Remove the CD and reboot.

The problematic Replicant will have been removed from your desktop, enabling you to boot normally again. Note that this will remove all Replicants that were on your desktop.

*Franco Martinez (PalmaServ@topmich.com) adds the following:
BeOS 5 PE Users (who lack the CD) can remove bad replicants by doing the following;
1) Running a search for the (tracker_shelf) file, once found the file can be deleted right from the search results window.
2) Press CTRL+ALT+DEL to bring up TaskManager and kill the Tracker itself.
3) Once the Tracker is dead and your desktop disapears, press the „Restart the Desktop) button in TaskManager and your desktop will return WITHOUT any replicants.
No re-boot required.