Risk of Email Attachments

Many people use email to communicate on a daily basis. It has many advantages over traditional, posted mail, including speed and the ability to write to several people at once. Email also allows users to send files in the form of attachments. These files can include family photographs or documents for your job. Email attachments may harbor more vicious content.

Email allows us to communicate efficiently, but also can expose you to unwanted risks.

Identification

• Your email provider, such as Hotmail, Yahoo! Mail or Gmail, or the email client you use, such as Outlook or Thunderbird, should alert you when an email has an attachment. Look for a paperclip symbol next to the subject or an attachment list.

Prevention

• You can prevent suspicious or malicious email attachments from wreaking havoc on your system by installing an anti-virus program that scans your incoming email. Norton, McAfee, BitDefender and Avast! are just a few of the many options for anti-virus software. Browser-based email providers, such as Hotmail, Yahoo Mail and Gmail, have an in-house scanner that tests attachments before you open them.

  
  
  

  Your email provider or client may have an option to allow you to read or preview the email message without opening the attachment. Most attachments need to be opened in order to damage your system.

  Be especially wary when you do not recognize the sender of an email. Although you might be expecting an attachment from someone you know, hackers and spam can also take over someone else's email account and send you spam or other unwanted attachments. It is best to take precautions with all emails; not just those from unknown senders.

  Be sure to always install the latest updates to your operating system.

  If you do open a risky attachment, your anti-virus program may block the attachment from harming your computer. However, prevention is the safest route.

Attachment Types

• There are many legitimate email attachments. If you recognize the sender, you may have an idea what the attachment contains.

  Photo attachments may have a file type of "Jpeg," "Bmp" or "Gif," while text document may be in "Txt" or "Doc" format.

  Additionally, you may recognize PowerPoint presentations as "Ppt" files and Excel spreadsheets as "Csv" files.

  Other file types include "Exe," "Com" and Vbs;" these executable files run an application on your computer and are potentially dangerous.

  Email users can archive a group of files into a folder type called "Zip." You must unzip the folder in order to access the files it contains. These files can be dangerous because you have no idea what the archive contains and your anti-virus program may not be able to scan the contents.

Risks

• Executable attachments can run unknown programs on your computer, destroy or corrupt data, steal and spread your personal information, decrease your computer's performance and even block anti-virus or anti-malware programs from working correctly.

  Attachments can include viruses that will infect your computer. Even a seemingly legitimate attachment can give you a virus. For example, SpamLaws, a security information website, describes the "ILoveYou" virus from the early 2000s as an attachment that disguised itself as an affectionate message that Internet users were likely to send to people they cared about.

  Worms are a type of malicious software that use up your computer time and bandwidth, essentially clogging computers and networks.

  Viruses can open your email address books, extract the addresses, and automatically email themselves to some or all of the addresses, according to The University of Essex website.

Reparation

• If you have clicked on an email attachment that released an executable file, virus or other malicious software on your computer, scan your system with anti-virus software as soon as possible. When your scanner catches the virus, follow the prompts to delete or quarantine the file.

  You may also want to scan your system with anti-malware software, such as Adaware or Spybot: Search and Destroy. These programs can detect malicious files that may not be viruses.

  Some malicious files may require you to download special removal software. Symantec, the creator of Norton, offers removal tools for certain, especially stubborn viruses and Trojans.

  If your anti-virus or anti-malware program detects the malicious file but cannot remove it, try running a scan in Safe Mode. Start Safe Mode by pressing "F8" immediately after starting your computer.