Email and email attachments can sometimes contain computer viruses or links to phishing websites. Before you trust an email message, do the following:
Install an antivirus program that can scan email attachments. Make sure the program is updated regularly.
Check the sender's address to make sure that you know the person or organization that sent the message, and that you're familiar with the address. A message from an unknown sender or address isn't necessarily dangerous, but you should be cautious before opening it.
Check the subject line of the message for suspicious language, such as gibberish or directions to open an attachment or click a link. Some viruses can mimic, or spoof, legitimate email addresses, and a suspicious subject line can sometimes alert you that an email message is fraudulent.
If the message has an attachment, scan it with an antivirus program. If the attachment contains an executable file that you weren't expecting to receive, you might want to delete the message without opening the attachment.
If the message is from a person you know, but you either weren't expecting it or suspect it might be fraudulent, then send a new email message to that person to verify that the message is legitimate.