Seven Things to Know About an Email Attachment

Starting here, you can learn the seven big things to know about an email attachment. A few of these things will be familiar to you if you have been using attachments in recent versions of Outlook.

The seven big things to know about email attachments are:

What is an Email Attachment?

An email attachment (attachment for short) is a file that is connected to, and travels with an email message.

Any type of file you can find on your computer can be attached to a message and sent along with it. Examples include:

  • Word documents
  • Excel spreadsheets
  • Scanned photos
  • Digital music files
  • and more

Some files are too big to work as attachments. Email systems have limits on the size of the attachments that they will allow you to send.

The size limits vary by email system, but are usually a few megabytes (MB). A word processing document or a spreadsheet or a single photo will almost always get through fine.

If you attach many photos to a message, or an MP3 music file, they may be too big. That pirated copy of the latest DVD? Forget it. Way too big.

Why does Outlook block some attachments?

As we just discussed, some files are too big to send as attachments. Outlook also stops you from sending certain file types as attachments. This happens regardless of their size. This is meant to protect you.

Attachments are a popular way that hackers get into computers. To help protect people against this, Microsoft modified Outlook. It now blocks a wide variety of attachment types. These are the types that hackers use to attack you.

Microsoft Office files and most image files (like those pictures of the kids) go through fine. But Outlook blocks dozens of other types of files. If you are curious about which file types Outlook blocks, this page has more information.

The problem is that Outlook may block an attachment that you need to send or receive. But there is a workaround. Whoever is sending the attachment should either:

  • Zip the file before sending it
  • Change the file extension (and tell the recipient what to change it back to after they receive it)
  • Transfer the file in some other way than email.

It is a pain, but having your computer infected with a virus would be even more so. Besides, you can't change the way Outlook handles attachments, so you have to make the best of it.

How to Add an Attachment to a Message

Adding an attachment to a message is simple. There are multiple ways to do it too.

If you are creating a new message that will have attachments, the easiest way to go is this:

  1. Open Outlook to Mail view.

  2. In File Manager or any other window, select the file or files you want to attach to the message.

  3. Drag the file(s) to any spot in the Inbox pane, and drop them there.

Outlook opens a New Message window with the files already attached. If you attached a single file, Outlook inserts the file name as the message Subject (see the figure below). If you attached multiple files, Outlook leaves the Subject field blank.

outlook attachments

You can also drag the file you want to attach onto an already-opened email message window and drop it.

Or you can use the Insert File button (it looks like a paperclip) on the message toolbar to open an Insert File dialog box, then navigate to the file or files you want to attach.

In any of these cases, when you finish, your attachment or attachments will show up in the Attachment text box in the message header, as shown in the following figure.

A message with an attachment.

Once you attach the file to the message like this, you are all set.

When you send the message, the attachment will automatically travel with the message to the recipient, assuming the email system doesn't block the message because the attachment is too big, and Outlook doesn't block the attachment to protect the recipient.

How to Open an Attachment You Receive

If you receive a message with an attachment, you will see a paperclip next to the message subject in the mail pane. In the Reading pane and if you open the message, icons for any attachments will appear in the message header.

This message has an attachment.

In any version of Outlook, you can go to the File menu and click Save Attachments to save any or all of the attachments to your hard drive.

In Outlook 2003, you can double-click an attachment icon to open that attachment in the appropriate program (Word documents in Word, photos in your default graphics progam etc.). In Outlook 2007, things get a little more complicated, and you should visit the page on previewing attachments for more information.

From here you can: