OL97: Mail Attachment Security Add-in Available on Web

ID: Q165116

The information in this article applies to:

SUMMARY

Microsoft provides a mail attachment security add-on for its mail clients. The mail attachment security add-on warns you before an attachment is opened so you do not unknowingly open a malicious attachment. You can download the add-on from the following location:

   http://www.microsoft.com/security/bulletins/mailaddon.asp

MORE INFORMATION

This add-on is designed for Windows 95 and Windows NT 4.x users who are running either Outlook 97, Microsoft Exchange clients versions 4.x and 5.x, or the Windows Messaging System client (the Inbox program that ships with Windows 95 and Windows NT 4.x).

Microsoft will distribute the attachment security add-on for Exchange clients for Windows 3.11, Windows NT 3.51, and the Macintosh as a part of the regularly scheduled Microsoft Exchange Server Service Pack releases.

A similar warning feature is available for the Internet Mail and Newsgroup client by downloading and upgrading to version 3.02 of Internet Explorer from http://www.microsoft.com.

The mail attachment security add-on warns you before an attachment is opened so you don't unknowingly open a malicious attachment. While most attachments are benign, it is possible to send programs or files that can cause damage to your computer. You can disable or bypass the warning for selected file types that you feel comfortable opening without warning as well as for executable code that is signed using Authenticode.

NOTE: This add-in does not prompt for Microsoft Excel or Microsoft word attachments and some file types, such as .exe and "unknown" file types always give a warning and cannot be disabled.

The security add-on is a self-extracting dynamic link library (dll) file that you can download from the Microsoft Security Advisor Web site at http://www.microsoft.com/security/.

NOTE: Because the Microsoft Web site is constantly updated, the site address may change without notice. If this occurs, link to the Microsoft home page at the following address:

   http://www.microsoft.com/ 

Microsoft will provide localized versions of the add-on as they are available.

When you attempt to open an attachment with the warning add-on enabled, the following warning appears:

   -----------------------------------------------------------------
   | Opening:                                                      |
   | Name of attachment file in "Name of message"                  |
   |                                                               |
   | Some files can contain viruses or otherwise be harmful to     |
   | your computer. It is important to be certain that this file   |
   | is from a trustworthy source.                                 |
   |                                                               |
   | What would you like to do with this file?                     |
   |                                                               |
   | O Open It                                                     |
   | O Save it to disk                                             |
   |                                                               |
   | [ ] Always ask before opening this type of file               |
   |                                                               |
   |                              OK         Cancel                |
   -----------------------------------------------------------------

To enable or disable the warning dialogs, do the following:

1. On the Tools Menu, click Options and then click the Attachments tab.

2. Select the option for warnings that you want.

Additional query words: add-in patch update

Keywords          : kbpatch kbdta GnlAddin 
Version           : WINDOWS:97
Platform          : WINDOWS
Hardware          : x86
Issue type        : kbinfo

Last Reviewed: April 20, 1999