Microsoft KB Archive/224567

= Word macro virus alert "Melissa Macro Virus" =

Article ID: 224567

Article Last Modified on 1/24/2007

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APPLIES TO


 * Microsoft Word 97 Standard Edition
 * Microsoft Outlook 98 Standard Edition

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This article was previously published under Q224567





For a Microsoft Word 2000 version of this article, see 224506.



SUMMARY
This article contains important information about the Microsoft Word macro virus that is named "Melissa". The following topics are covered in this article:
 * Whom can the virus affect?
 * What is the "Melissa" macro virus?
 * Will Office 97 protect my computer from this and other macro viruses?
 * How do I ensure the Office macro virus protection is turned on?
 * How do I ensure my computer will not be infected?
 * What should I do if my computer has been infected by this virus, or I think it has been infected?
 * What if I have more questions about macro viruses?



MORE INFORMATION
On March 26, 1999, Microsoft was made aware of a Word macro virus W97M/Melissa.A (dubbed "Melissa") that has affected a number of users and companies. As with all security issues, Microsoft takes this very seriously, and because of the widespread nature of this particular virus, Microsoft is taking steps to proactively notify our customers to help minimize its impact. By taking the necessary precautions, you can ensure it does not affect your computer.

Whom can the virus affect?
This virus can affect people who are using Word with Outlook 98 or 2000. If you do not use this software, this particular virus does not affect your computer.

What is the "Melissa" macro virus?
It is a Word macro virus delivered via e-mail in an attached Word document. The e-mail message contains the subject line "Important Message From "UserName" and/or contains the message body "Here is that document you asked for ... don't show anyone else ;-)". If the attached Word document is opened and the macro virus is enabled (that is, it is allowed to run), it can propagate itself by sending e-mail with the infected document to a number of recipients. The virus reads the list of members from each Outlook Address Book and sends an e-mail message to the first 50 recipients programmatically.

The name of the original infected Word document is List.doc, but this could be changed to any name. After the virus has been enabled and allowed to run, it can infect your default template (Normal.dot). New documents are based on the Normal.dot template, so they too can become infected. In this scenario, you could create a new document, send or give the file to someone, and their computer could then become infected. The virus would then attempt to send your document (instead of the original infected List.doc file) out to 50 recipients from each Outlook Address Book.

This virus does not appear to destroy data. If the current day of the month equals the minute value of the current time, and the infected document is opened, the following text is inserted at the current insertion point position:

Twenty-two points, plus triple-word-score, plus fifty points for using all my letters. Game's over. I'm outta here.

Will Office 97 protect my computer from this and other macro viruses?
Yes. Word 97 will protect your computer from macro viruses, including this one, provided the macro virus protection is turned on (this is the default setting). With the macro virus protection turned on, every time you receive a Word document that contains macros, a dialog box opens and allows you to choose whether to enable the macros. You should always disable macros when you are not certain of their purpose or functionality. By choosing to disable the macros, you will prevent this and any macro virus from running, rendering them harmless. The virus is only activated if you open the attached Word document and choose to enable the macros or if your macro virus protection settings have been turned off.

How do I ensure the Office macro virus protection is turned on?
In Word 97, do the following:


 * 1) On the Tools menu, click Options.
 * 2) On the General tab, select Macro Virus Protection.

Important Note If you are not able to follow the steps above because you cannot find the menu items, your computer may already be infected. If so, run anti-virus software containing the latest update and scan your system often. Support for this particular virus is already available from a number of anti-virus vendors. If you are not able to run anti-virus software, it will be necessary to delete or rename your Normal.dot file. This is the Word global template that is automatically recreated after Word is started. After this is done, repeat the steps above.

For additional information about how to delete or rename the Normal.dot template, click the following article number to view the article in the Microsoft Knowledge Base:

181079 WD97: What to do if you have a macro virus

How do I ensure my computer will not become infected?
Ensure the Office macro virus protection is turned on as described above. Always choose "disable macros" when asked, if you are unsure of the purpose of the macro in the document. Doing so will still allow you to open the document and read its contents. Once you are certain the macro is safe, and only if you need to run that macro, you can then re-open the document and enable the macro.

Run the latest anti-virus software, and scan often. This is how you can ensure that the macros in documents are safe. Disinfectors for this particular virus are already available from a number of anti-virus companies. Also remember to keep your anti-virus software up to date by installing the latest signature files for that company. (Most companies creating anti-virus applications release a new signature file each month.) For additional information about antivirus software, click the following article number to view the article in the Microsoft Knowledge Base:

49500 List of antivirus software vendors

What should I do if my computer has been infected by this virus, or I think it has been infected?
Run anti-virus software containing the latest update, and scan your system often. Support for this particular virus is already available from a number of anti-virus companies.

Ensure your Office virus protection is turned on. After the virus has been allowed to run, it will disable the virus protection in Word. Remember to make sure Office macro virus protection is turned on by performing the steps listed above.

What if I have more questions on macro viruses?
For additional information about macro viruses, the "Melissa" virus, and vendors of antivirus software, click the following article number to view the article in the Microsoft Knowledge Base:

163932 WD97: Frequently asked questions about Word macro viruses

Or visit the following Web sites:

http://office.microsoft.com/en-us/assistance/HA010450611033.aspx?amp;CTT=6&Origin=EC010553071033

http://www.cert.org/advisories/CA-1999-04.html

http://www.ciac.org/ciac/bulletins/j-037.shtml

Additional query words: infected disinfect protect protected infect prank w97m melissa.a email WD97

Keywords: kbdownload kbhowto KB224567

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