How do you make a new tab open in Explorer when a user clicks a link that has _blank in the link. The link opens a new explorer window not a new tab like in Firefox and Chrome.
Whether the link opens in a new window or a new tab depends on the browser's preferences. In the preferences of Internet Explorer, Firefox, and Chrome, look for an option that says something along the lines of:
Open links meant to open a new window in:
() the current tab/window
() a new tab in the current window
() a new window
Whatever that is set to will determine how a link with the target="_blank" attribute is handled. I'm not sure where that preference is located in the browsers that you're testing, and I don't have any of those browsers installed to check, but it should be easy enough to find.