 Many of the most common computer viruses and other malicious software are spread through e-mail attachments—the files that are sent along with an e-mail message. If a file attached to an e-mail message contains a virus, it's often launched when you open the file attachment (usually by double-clicking the attachment icon). You can help avoid some viruses by following a few basic rules. 5 tips for dealing with e-mail attachmentsFollow these basic guidelines when dealing with attachments in an e-mail message, no matter what e-mail program you're using: 1. | Don't open any attachment unless you know whom it's from and you were expecting it. | 2. | If you receive an e-mail message with an attachment from someone you don't know, delete it immediately. | 3. | Use antivirus software and keep it updated. Windows Live OneCare scans e-mail attachments as you open them. | 4. | If you need to send an e-mail attachment to someone, let them know you'll be sending it so they don't think it's a virus. | 5. |
Use an e-mail program with spam filtering built-in, such as Microsoft Office Outlook 2007, Windows Live Hotmail, or Windows Live Mail. |
Dealing with e-mail attachments in Microsoft OutlookMicrosoft Outlook can block potentially unsafe attachments before they get to you. For example, if you're using Outlook 2003 and you receive an e-mail with an attachment that could contain a virus, you'll see the warning below.  An example of an e-mail attachment blocked by Outlook 2003. If you know that an attachment is safe and need to know how to unblock it, see About unblocking attachments. If you'd like to learn more about why Outlook blocks certain attachments and not others, see Blocked attachments: The Outlook feature you love to hate. Dealing with e-mail attachments in Outlook ExpressIf you use Outlook Express, you can greatly increase your chances of avoiding viruses, worms, and Trojans by upgrading to Windows XP Service Pack 2 (SP2). With SP2, Outlook Express will block potentially harmful attachments by default and has numerous other features that help prevent viruses and other malware. If you use Outlook Express, but you're not sure what operating system you're running, visit Find out which operating system your computer is using. If you're not using Windows XP SP2, you can check your virus protection settings manually. To ensure your e-mail virus protection is turned on in Outlook Express 1. | On the Tools menu, click Options. | 2. | Click the Security tab. | 3. | Select the Do not allow attachments to be saved or opened that could potentially be a virus check box. | 4. | Click OK. |
To open an attachment that you know to be safe 1. | On the Tools menu, click Options. | 2. | Click the Security tab. | 3. | Clear the Do not allow attachments to be saved or opened that could potentially be a virus check box. | 4. | Click OK. | 5. | Close and reopen the message with the attachment that you know to be safe. | 6. | Open the attachment. | 7. | Repeat Steps 1 and 2. Then select the Do not allow attachments to be saved or opened that could potentially be a virus check box. |
If you're running Windows XP SP2 you may be given one more warning, such as the one you see below.  Security warning Always use caution before clicking Run, as that could install a virus or other potentially dangerous program.
| 
