After installing new Logitech drivers for my MX-1000 mouse, all is fine until I have rebooted few times. After that, I always have driver loading errors after login. So there is a simple solution. It seems that the Logitech installer uses a wrong group name (admin instead of wheel).
To fix it, type this in the Terminal:
sudo chown root:wheel -R /System/Library/Extensions/LogitechUSBHIDevices.kext
Reboot, and all should be fine.
Mac OS X Hints
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