The 50,000+ subscribers of Google’s Video e-mail group should double check their computers. CNET’s News.com reported the security blunder Wednesday. On Tuesaday, three postings were made an e-mail list the send alerts to the group. “Some of these posts may have contained a virus called W32/Kapser.A@mm–a mass-mailing worm,” Google said in a note on its Web site.