Rather oddly, I don't think you can. Tasks seem to be either scheduled or run once at restart and (or some other things), but not both. Logically I cannot see why not, particularly as the 'run at restart task' reverts to manual after it has been run. So, unless Joel advises that there is a particular logic in the current arrangement, I'll raise a Trac ticket for an enhancement.
At startup is possible, but at shutdown will be a problem. Windows will prevent programs from "buying time" from the OS during shut down. After a while it'll just pop up the delay dialog and ask the user to force the tasks to exit.
Since this is a behaviour change, it'll only be implemented in Eraser 6.2
Hi Joel and Eraser team. What about adding a right click option, when right clicking files, for "batch erase" or something. Then add a option in Eraser setting with a check box to shutdown after "batch erase" Finally, add a right click to the Eraser tool try icon to "start batch erase". This would allow us to queue up eraser tasks, tell Eraser to shutdown automatically after batches are done, and kickoff the batch easily by right clicking the icon in the tool tray. (a dos command to kick off the batch would also be nice, so we could create a shortcut or something as well.)