If many tabs are openned in the Internet Explorer, a balloon pops up when you close the window, asking that if you want to "Close all tabs" or "Close current tab".
Some students check "Always close all tabs" carelessly. As a result, no prompt pops up when they close many tabs. What shall we do do recover the prompt?
Things we can do:
Press "Alt+T", and click "Internet Options".
In "Tab" column, click "Settings" botton.
Open "Tabbed Browsing Settings" window, and check "Warn me when closing multiple tabs".
Finally, press "OK" to exit the settings window.
If it does not work all the same, you are suggested to dig the Forum to see if any solution can be best for you.