Actually, your worst fears about the evil Back Button, though perhaps initally griped in jest, are well deserved.

There is a security bug in Microsoft Internet Explorer that allows scripts to be embedded in URLs. When you press "back" from a "Local" Internet zone such as an error page, the script is executed in the Local zone. A malicious web site could then read files on your computer, execute programs, and delete your 20 page E2 writeup drafts.

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