Malicious emails often attach various forms of executable programs and trick users into running them. These include standard Windows executables (.exe), batch files (.bat), and even JavaScript ...

The service will start blocking JavaScript file attachments starting on February 13th, adding it to its list of restricted file types, which includes .exe, .msc and .bat.

Starting February 13th, however, another file type will be joining that group: .js. .js files are commonly associated with running client side JavaScript code on a webpage, so the average user ...

Similar to how it handles other restricted attachments, if you try to attach a .js file to an email on or after the 13th, you'll get a notification that says it's blocked "because its content ...