Zip or unzip a file

Applies to
Microsoft Office System

Compressed file

Why zip a file?

Zipping a file creates a compressed version of the file that is considerably smaller than the original file. The zipped version of the file has a .zip file extension. For example, if you zip a Microsoft Office Word document called Government Proposal.doc that is 6.5 megabytes (MB) in size, the file created, Government, is reduced to 2.5 MB. File types that are reduced the most as a result of zipping are text-oriented file types, such as .txt, .doc, .xls, and graphics files that use non-compressed file types such as .bmp. Some graphic files, such as .jpg and .gif files, already use compression; therefore, the file size is reduced very little by zipping. Also, a Word document that is full of graphics files does not get reduced as much as a document that is mostly text.

 Note   Creating a .zip file is also known as "archiving" but has nothing to do with archiving in Microsoft Office Outlook.

Some advantages of zipping a file are:

  • You save storage space. Zipping large files can save up to 80 percent or more in hard disk space.
  • Smaller file size drastically reduces e-mail transmission time.
  • The smaller file size of e-mail messages that you want to keep is useful when your mailbox has a space limit.
  • Many zip utilities allow you to encrypt files and protect sensitive data, especially when you send it in e-mail.
  • You can send and receive e-mail attachments, such as .exe files, that would otherwise be blocked by Outlook for security reasons.
  • Many zip utilities support disk spanning, which means when you create a .zip file on a removable disk and run out of disk space, the utility prompts you to insert additional disks as needed and then continues the process.
  • Many zip utilities allow you to create a self-extracting archive. These are archives that compress and package the files that you specify as an executable (.exe) file. When you click the executable file to open it, the .exe has the ability to extract the files from within itself and produce the original files.

 Note   By default, .exe attachments are blocked by Outlook.

Who makes zip utilities?

There are a number of excellent zip utilities available that have good Help systems and supporting Web sites, including the following: PentaZip, PicoZip, PKZip, PowerArchiver, StuffIt, and WinZip.

 Note   Several of these are represented in the Microsoft Windows® Catalog and on Microsoft Office Marketplace. For more information, see the See Also section in this article.

If you are not sure which utility to use, most programs offer a 30-day limited trial period where you can download and try the utility for free.

 Important   The information in this article is general. For specific information on features and "how to" procedural steps, see the documentation that comes with your zip utility. Some zip utilities have both a "classic" interface and an easy to use "wizard" interface. Most come with a Help system in addition to FAQ articles and other guides on the software vendor's Web site.

Integration with Windows Explorer

After they are installed, many zip utilities integrate with Windows Explorer in Microsoft Windows XP so that when you right-click a file, zip commands are available on the shortcut menu.

Right-click shortcut menu

Zip a file

To create a .zip file, right-click a file, such as Government Proposal.doc, and then click a command on the shortcut menu, such as Add to Zip file or Add to Archive, to create Government Often the zip utility shortcut menu also includes a command such as Configure or Options to access the zip utility's option settings.

Unzip a file

To unzip a file, right-click the file, such as Government, and then click Extract on the shortcut menu.

Integration with Outlook

Most zip utilities work with Outlook to facilitate sending and receiving attachments as .zip files.

Send a zipped attachment

If you want to send an attachment, such as a .zip file, do the following:

  1. In Outlook, open a new message.
  2. Click in the body of the message, and then click Insert File Button image.
  3. Do one of the following:
    • If the .zip file, such as Government, already exists, double-click the file to insert it into the message.
    • If the .zip file doesn't exist, right-click the file that you want to zip, such as Government Proposal.doc, and then on the shortcut menu, click the zip utility's command for sending a .zip file in e-mail. Doing this converts the file to a .zip file, such as Government, and inserts it into the message.
  4. Compose your message, and then click Send.

Right-click shortcut menu

Send all attachments as .zip files automatically

If you want to attach a regular file, such as Government Proposal.doc, in the usual way and always have it sent as Government, you can configure most zip utilities to do this automatically. See the utility's option settings and documentation.

 Important   If you don't want attachments to be automatically zipped, turn off that setting in the utility. If the behavior persists, make sure that you not running another zip utility or add-in program. On the Tools menu, click Options. On the Other tab, click Advanced Options. In the Advanced Options dialog box, click COM Add-Ins. In the Add-Ins available list, check to see if there is a utility that is causing the behavior. If yes, clear the check box next the the utility name to disable it or click the utility, and then click Remove.

Open a zipped attachment

To open a zipped attachment, double-click the attachment.

Outlook attachment

  • In the Opening Mail Attachment dialog box, if you click Open, the zip utility automatically unzips the file for you if the utility is configured to do that; typically this is the default setting.
  • If you click Save, you can save the .zip file to the location that you want by using the usual Windows Save As dialog box.

Compressed folders in Windows XP

Windows XP has basic built-in zip capability so that you can compress files by using the Compressed (zipped) Folder feature. Folders compressed by using this feature are identified by a zippered folder icon.

Zip compressed folder

You can either create a compressed folder, and then move or copy the files to that folder to compress them, or you can right-click a file, point to Send on the shortcut menu, and then click Compressed (zipped) Folder.

Compressed zipped folder

Compressing folders by using the Compressed (zipped) Folder feature does not decrease your computer's performance. Compressed folders can be moved to any drive or folder on your computer, and you can work with a compressed folder and the files or programs that it contains just as you would an uncompressed folder.

You can open files directly from compressed folders, or you can extract files before opening them.

Extract all files

 Note   You can run some programs directly from compressed folders, without decompressing them. However, to run programs that are dependent on other files, you must first extract them.

You can send a compressed folder in e-mail by clicking E-mail this file in the File and Folder Tasks pane.

E-mail this file

If you use the Windows "classic" view, you can right-click the file, point to Send To on the shortcut menu, and then click Mail recipient.

So are you ready to get started with zipping and unzipping files? Keep in mind that the information in this article only covers the basics. Most zip utilities offer many more features than have been described here. Visit some of the Web sites mentioned earlier in this article and see which zip utility will work for you.

Applies to:
Access 2003, Excel 2003, FrontPage 2003, InfoPath 2003, OneNote 2003, Outlook 2003, PowerPoint 2003, Publisher 2003, Word 2003