The Department of Homeland Security is warning Americans to stop using the Web browser Internet Explorer because it has a bug that could allow hackers to install malicious software without the user knowing it.

The vulnerability, the United States Computer Readiness Team says, has already been exploited in the wild.

A number of people have already been victimized by a new scam in which fraudsters pose as callers from Microsoft. They insist that your system has a virus or is running too slowly, and have you not only pay for a bogus
service, but steal your credit information as well.