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WinZip Express for Outlook

WinZip® Express for Outlook makes it easy to share files via the cloud, directly from Outlook, by compressing attachments into a Zip file, uploading the Zip file to the cloud, and inserting a link into your email. It helps you overcome email attachment size limits, provides extra security with encryption, and allows you to convert Office documents to PDF, as well as to watermark and resize images.

Requirements: WinZip Express for Outlook requires Outlook 2013, 2016, or 2019 and an installed and registered copy of WinZip 18.0 or later.

Starting WinZip Express for Outlook

WinZip Express for Outlook starts automatically when you open Outlook. When you create a new email message, you will see the WinZip Express group in the message window ribbon:

Outlook Express main

The WinZip Express group determines how WinZip Express handles file attachments.

Attaching files

The Use Cloud Services menu

The Use Cloud Services dropdown menu determines whether your attachments are compressed and shared via cloud links, and which cloud service to use:

cloud drop down

The first section determines whether attachments will be compressed and shared via the cloud:

  • Use for this message: When you click Send, WinZip Express zips your attachments (applying any optional conversions), uploads the Zip file to a cloud storage service, removes the attachments from the email, and inserts a link to the uploaded Zip file into the email text. Your recipients simply click the link to download the Zip file containing your attachments.

  • Use if files exceed configured limit: When you click Send, WinZip Express checks to see if the total file size exceeds the configured size limit (5 MB by default). If the size is greater than the limit, WinZip Express performs the same steps as it does when Use for this message is selected; otherwise they are left as attachments. You can change the size limit in WinZip Express options.

  • Do not use for this message: The files are left as attachments to the email.

Below this is the Add Cloud drop down menu, which will display the Services to which you are currently logged in first, with an indication of the amount of free space available. Other services are listed below the logged in services. Click the service that you want to use. If you are not logged in to the selected service, you will be given an opportunity to log in.

The currently selected service (OneDrive in the picture above) is shown with a highlighted icon.

Note: If you have not already selected a default cloud service in WinZip Express options, there will also be a Save selection as default entry in the menu, checked by default. If you do not want the service you select here to be the default, uncheck the entry. Remember that you can always change the default cloud service in the options dialog.

Attach Large File

Attach Large File opens a window that allows you to select files to send using the cloud. This is especially useful when Exchange prevents you from attaching a file due to size limits.

When you use Attach Large File, instead of attaching the actual files to your email message, WinZip Express attaches small, temporary placeholder files to the email message to denote which files should be zipped and uploaded to the cloud. When you click Send, WinZip Express zips the selected files (applying any optional conversions), uploads the Zip file to the cloud, and then inserts a link into the email so that your recipients can download your file.

Note: When Attach Large File is used, WinZip Express will always zip your selected files and use the cloud to deliver your files, regardless of any other options.

Encryption and other conversions

The remaining four buttons enable or disable optional conversions, which are applied to your attachments if and when they are being zipped. Any conversions that are currently enabled are shown with a highlight (Resize Images is enabled in the image of the WinZip Express ribbon group near the top of this page).

  • Encrypt Upload: Enable this option to encrypt files as they are being added to the Zip file. WinZip Express will ask you for an encryption password when you click Send. The type of encryption is determined by your options (see below).

  • Convert to PDF: Enable this option to convert documents (.doc, .docx, .xls, .xlsx, .ppt, and .pptx files) to PDF format as the are being added to the Zip file. Conversion options are determined by your options.

  • Reduce images: In addition to the compression that WinZip Express provides, another way to reduce the size of your attachments is to make pictures and other images smaller before they are added to the Zip file. Enable the Resize images option to do this. The size to which the image will be resized is determined by your options. Note that images smaller than the selected size are not resized; image resizing only makes pictures smaller, never larger.

  • Watermark images: Enable this option to add a custom watermark to PDFs, pictures, and other images added to the Zip file. The watermark image that will be used, along with other watermarking options, is determined by your options.


Everything that WinZip Express does is configured in one place, in the WinZip Express group in Outlook's File tab. Simply click the Express button and then Options:


This displays the WinZip Express Options dialog:


The options are:

Cloud Service

  • Click Cloud Options to display the cloud options dialog, where you can set the default cloud service and the default setting for Use Cloud Services.
  • Click one of the radio buttons to tell Outlook Express to either work Always, When attachments are larger than a configured size, or Never.
  • Click the Encrypt uploads box to have all attachments be zipped and encrypted.
  • Click the Encrypt options button to set the encryption strength.

Compression Type

Choose what kind of compression you would like WinZip Express to use:

  • Zip: Legacy (Zip 2.0): Choose this option if you frequently share your files with others who may be using older Zip file utilities. The compressed files may be larger than they would be if compressed with the Best Method option, but your recipients will be able to use any Zip file utility to view them.

  • Zipx: Best method (smallest size): Choose this option to provide optimal compression for minimal use of storage space. Best method uses a special compression method that compresses JPEG pictures better than other methods with no loss of picture quality (there is no loss of picture quality with any WinZip compression method). Choosing Best method will result in a .zipx file. To extract these Zip files, your recipients will need WinZip 12.1 or later.


Check any conversions that you would like applied by default. Note that these are simply defaults—you can change which conversions are applied for each individual email message as described above.

Click the options buttons to set preferences for the conversions:

  • Convert to PDF by default: Click to set preferences for converting documents to PDF files.

  • Reduce images by default: Click to set the desired size for image resizing.

  • Watermark by default: Click to specify the watermark text, transparency level, and other watermarking options.

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