Problems starting up after recent Security Updates? Try removing DoubleCommand

We've received reports from some readers indicating problems starting up after applying either Security Update 2006-007 or Security Update 2006-008 or both that are resolved by removing the utility DoubleCommand -- a kernel extension that lets you rearrange many modifier keys for the layout you want.

As noted in our tutorial "Startup fails (particularly after a system or security update); solving," kernel extensions -- especially those that load via files in the /Library/StartupItems -- can sometimes create conflicts with newly applied system updates, causing problems with startup and other operations.

If you have installed DoubleCommand and are having startup issues after applying one or both of the aforementioned security updates, use the following process to remove the software and check for persistence of the problem:

1. Delete the DoubleCommand folder in /Library/StartupItems on your Mac OS X startup volume.
2. Delete the DoubleCommand preference pane in /Library/PreferencePanes on your Mac OS X startup volume.
3. Restart your computer.

Feedback? Late-breakers@macfixit.com.

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