In the early 2000s, many security personnel recommended disabling your email client's preview feature. Just previewing an email can be dangerous! This is no longer good advice. With a modern email client, you can preview any email you want.
If you don't have a time machine, it's safe
We've recently published an article on how to enable the preview box in Gmail. Through article comments, e-mail messages and Twitter DMs, we got a few people who asked if it was safe to use the preview box.
Previously, articles that were advised to disable the preview box were common. Many websites made it possible to use the preview box was a bad idea. They often did not specify why other than saying you "can open an email that you really do not want to open." The meaning is that a virus or other nasty thing can come on your computer if you open an infected email. To be fair, it was a problem for a short while back in the early millennium.
But the most important e-mail developers of the time, including Microsoft, Pegasus, Eudora and Apple (there was no Gmail right now), got very fast. Within a few years, the problem was almost gone because all mail clients stopped allowing code to be executed when an email was open. No mail client now allows the code to be executed when you open an email, and they have not allowed it for over a decade. So, if you don't use a very, very old, unchanged email client (think of Outlook Express circa 2000 on a Windows 98 machine), your email program simply can't allow code to run when you open an email.
If you are not
RELATED: How to enable the Gmail preview box for hidden email
Here is the real danger
At the top of this article from the beginning of 2000 number with a time machine. Of these, all major email account providers, including Microsoft, Apple, Gmail and Yahoo! have sophisticated virus and malware detection tools that stop viruses and malware anyway to your inbox. It does not mean that there is no threat to email, but the threat requires you to do something like opening an attachment or clicking on a link. Worrying is that there are temporary articles that indicate that the preview box is a danger, but we do not recommend following such obsolete and incorrect advice.
The problem no longer exists, so by turning off the preview box, the only thing you do is make life harder for yourself.
As we have said before, it is possible to open e-mail messages. The risk comes from the following phishing links and opens dangerous attachments. These risks are the same if you use a desktop client such as Microsoft Outlook or web-based email such as Gmail.
If your e-mail client or browser contains an unmatched security hole, malicious e-mails can be exploited, you feel good. It should not be the case – you should use a current email client and web browser. Do not use an old, no longer updated email client. (You'd be surprised at how many people are doing.)
So yes it is safe to use the preview box and you can enjoy the productivity boost that gives you!  Why can't you get infected by opening an Email (Anymore)