Having reviewed both of the log files you attached, it is clear that in the case where your mouse is not functioning that it is not responding on the USB bus.
This is almost certainly a hardware problem; I have a similar mouse and if it's sleeping, I need to wake it up before the computer can detect it (at which point it is added to the USB bus). Check that your /etc/X11/xorg.conf uses /dev/input/mice (the default) so that X can cope when the mouse isn't connected until after the server is running. It could be possible that a combination of your hard drive and mouse is causing problems for your computer, for example too much power could be being drawn or a bad combination of USB 1.1 and 2.0 devices. There's no evidence here of a software problem in udev. Another possibility is that there is a kernel USB subsystem bug, or at least it's unable to handle this hardware situation. Check /var/log/dmesg for interesting errors during a boot where your mouse does not work. If you find any, please feel free to reopen this bug and reassign it to linux- source-2.6.17 ** Changed in: udev (Ubuntu) Status: Needs Info => Rejected -- mouse works _sometimes_ https://launchpad.net/bugs/55952 -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs