When I clicked on a new email subject in my online Yahoo mail inbox, my computer immediately shut down and re-booted itself before I even saw any email content. Was this just a random thing or was this some malware doing something to my computer before NOD32 v3 even had a chance to do anything. Nothing was downloaded and no attachments were opened. I just clicked on the email that I was going to open. My browser is Firefox. I subsequently ran a NOD32av scan and also scanned with Microsoft Malicious Software Removal Tool and with AdAware. These did not find any malware. I trust NOD32 but this seems to bizarre to ignore. I do not know what else to try or look for.