Right, this seems to be an electrical problem then; in your first dmesg outputs there were a lot of bus resets, which usually happen if the device gets into an undefined state (common for brownout).
** Changed in: hal (Ubuntu) Status: New => Invalid -- usb toshiba 80 GB detachable HD not getting mounted, not getting creted any device file https://bugs.launchpad.net/bugs/109563 You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs