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Zendio tracks when e-mails are opened, clicked on

For $10 a month, the Zendio add-on for Microsoft Outlook tracks what happens to the messages you send, including times opened and clicked on.

Who uses those receipts for e-mails read? Most people either block sending receipts altogether or ask to be notified before sending a read receipt (a default setting in Microsoft Outlook and other mail clients). So read receipts either don't work at all, or they require acceptance by the recipient--no sure thing.

That doesn't mean that we aren't curious about when the messages we send are opened, and when the links they include are followed. For most organizations, this information can be a valuable asset. The Zendio add-on for Microsoft Outlook tracks the messages you select and records the time the e-mail was opened, as well as when any of the links in the message were clicked.

Zendio also records the recipient's Internet Protocol address and shows the person's general location on a map. The program accomplishes this without the recipient knowing. That's right--the person who sent you that e-mail may know when you opened it, whether and when you clicked its links, and your general location. Creepy.

At $10 a month, Zendio is clearly intended for professionals, but you can't be sure when the senders of the e-mail you receive are recording your subsequent actions and location. Even if senders can determine some or all of this information via other means, Zendio makes collecting such data trivially easy.

The service also allows you to receive text alerts on your phone when a message is opened. A nice added feature is the Zendio Stationery Creator, which enables you to use and customize dozens of mail templates in such categories as Medical, Automotive, Law, Real Estate, and General Business.

Mail-tracking options on an Outlook toolbar
Zendio works with Outlook 2003, 2007, and 2010--I tested it on Outlook 2003. Before the program would install on the test system, the installer prompted me to load two other programs: "Microsoft Outlook 2003 Primary Interop Assemblies" and "Microsoft WebServices Enhancements (WSE) 3.0."

Once these programs installed, the Zendio toolbar was added to Outlook 2003. In Outlook 2007 and 2010, Zendio Options appear in the ribbon, as shown on the Zendio How It Works page.

The Zendio toolbar in new messages has buttons for tracking the message and its links, receiving alerts on your phone, applying a stationery template, previewing the message, and configuring your cell phone to receive alerts.

Zendio toolbar in a new Outlook message
The Zendio toolbar for Outlook lets you track outgoing messages to record when they are opened and when links they include are clicked. Screenshot by Dennis O'Reilly/CNET

After the tracked messages are sent, click the Tracking button on the Zendio toolbar in the main Outlook window to open the Zendio Tracking Inbox. Select one of the messages in the top window to view a summary of the e-mails sent to that recipient and a chart showing the best time to contact the person.

Zendio Tracking Inbox
The Zendio Tracking Inbox lists the tracked messages sent to each recipient and charts the best time to contact the person. Screenshot by Dennis O'Reilly/CNET

Click the View Read Data tab in the bottom-left window to see the date and time the message was opened and the approximate location of the recipient. The person's location is also shown on a map in the bottom-right window of the Tracking Inbox.

Zendio Tracking Inbox recipient location
The Tracking Inbox shows the approximate location of the recipient when the tracked message was opened. screenshot by Dennis O'Reilly/CNET

Clicking the View Link Data tab in the bottom-left window of the Tracking Inbox lists the links in the message, along with the date/time and the location of the recipient (the location is also shown on a map). Click Details to view the area code, postal code, organization, IP address, and Internet service provider.

Give your e-mail a professional look with customizable templates
In the past, I have recommended sending and receiving all mail as plain text to avoid malware that can infect your machine simply by opening an HTML message. This precaution is becoming increasingly impractical, as businesses in particular depend on HTML mail. One of the simplest ways to give your messages a professional appearance is by customizing one of the dozens of specialty templates offered by the Zendio Stationery Creator.

Browse the templates in the half-dozen categories, select one to your liking, add your information and images, adjust the color scheme using the built-in options, and click Save to add the template to the toolbar's drop-down menu in new messages.

Zendio Stationery Creator
The Zendio Stationery Creator lets you customize one of the service's dozens of templates to give your messages a professional appearance. Screenshot by Dennis O'Reilly/CNET

When you're ready to send the mail, click the Preview button to see what it will look like with the template applied (the message is automatically previewed before transmission, though you can uncheck this option).

E-mail recipients don't know they're being tracked
Despite the many legitimate uses for a service that tells you when the e-mails you send are opened, when the links in them are clicked, and where the recipient was when the actions occurred, the potential for misuse is tremendous--especially since the recipient has no idea the message sender is collecting this information. To discourage spammers, Zendio allows no more than 50 recipients for any single tracked message. The company also monitors traffic (though the messages don't use Zendio servers) to ensure that its customers aren't spamming.

Zendio's tracking uses an invisible image beacon in the message to report back when the message is opened and links are clicked, so if you view mail in plain text or disable images, the Zendio mail you receive won't be trackable--until you click a link. Alternatively, you could copy and paste the link into the browser address bar to avoid being tracked, but there's no way of knowing that the message is being monitored by the sender short of the sender disclosing the information.

Obviously, the information Zendio collects about e-mail recipients is valuable, and the product is straightforward and simple to use, but the lack of full disclosure is troubling. The company's efforts to prevent use of the service by spammers are commendable, but the potential for misuse of the service is tremendous. For example, imagine people determining their exes' whereabouts by sending them a tracked e-mail.

It may not be long before someone develops a tool that alerts e-mail recipients to the presence of a tracking beacon in the messages they receive. But just knowing that the person sending me a message may know when I opened it, which links I clicked (and when I clicked them), and my general location at the time gives me the willies. Now we have another reason for disabling images in e-mails from unknown recipients and copying and pasting rather than clicking the links the messages include.