Recently Google has announced that they will block all kinds of JS (Javascript) attachments in both the incoming and outgoing email messages starting from the February 13th, 2017. This is being done in order to make Gmail much more secure as the JS attachments are often used by spammers and cyber-criminals to steal your personal information or to carry out spear phishing attacks. Yahoo Mail is already very strict about these JS attachments. If someone sends you an email message containing JS attachments, Yahoo Mail servers simply reject the email message.
But if you use an email client like Mozilla Thunderbird to receive your email messages, then you may want to make sure that Thunderbird also stays secure. Here is how you can make Thunderbird secure:
- Click on the menu icon and select View → Display Attachments Inline (to uncheck this option) to make sure that all the attachments are not displayed inside the email message body.
- Click on the menu icon and select View → Message Body As → Plain Text to prevent any HTML content from being loaded in the message body.
- Click on the menu icon and select Options → Options. In the Options window, select Privacy section and then make sure that checkbox Allow remote content in messages is unchecked.
The overall effect of these settings would be that no harmful content will be able to load or run from inside the email message body. However this will prevent the email messages with HTML content with images and animations to be loaded.
To further protect your computer from malicious email messages, you should also install a good antivirus and firewall solution. You can install the free Zonealarm Antivirus that comes with the firewall protection as well. Some other security solutions also provide email message scanning that can stop malicious attachments and remove them before they can cause any harm.