Hmmm could be that you have selected shutdown after tranfers or minimize to system tray.

In LW tool>options>shutdown ---- shutdown immediately --- select this option, if you want.

Not sure what is causing your IE to cause an illegal operation or to reboot. Could be a number of things.

I would suggest to do some routine maint., disk clean up, disk defragmentor also run scandisk to see if there are any problems on your hard drive.