In response to the recent proliferation of email-borne viruses, Microsoft will add automatic blocking tools to the next version of its Outlook email application.
Outlook 2002 will have settings to automatically block 39 types of file attachment, meaning that under default settings, users will not be able to receive files such as images and screensavers.
However, it also means that attachments that have a legitimate business use - such as Java, HTML application files and executable program files - will also be blocked.
Although files to be blocked are set in the default settings, Microsoft said that administrators could create exceptions for each user, if required. There is also the option for creating "trusted add-ins", meaning that if a program has a certificate from the IT department, it can be accepted.
Outlook will also block Visual Basic scripting files. Microsoft has in the past been criticised by antivirus companies because Visual Basic is used by a large number of virus writers, and offers an easy route to creating viruses.
Should a virus writer find a way to circumvent the filters, Outlook 2002's Object Model Guard can also block access to the address book, and block the automatic sending of infected email. The additions made to Outlook are important because of the way that many email viruses self-propagate.
Microsoft said that Outlook 2002 will be available later this spring. The package will allow users to access their email via their corporate mail accounts or POP3 dial-up accounts.
Last week, law firm Beachcroft Wansborough urged business to consider taking out insurance cover against liability for problems caused by email. However, it said that companies could only get cover if their employees were properly trained in processes for email security.
