Bill Gates has confessed that it was a mistake to set "Control-Alt-Delete" as a way to log in to Windows.

During a talk at Harvard, Gates said that there was an option to make a single button for such a command, but the IBM keyboard designer didn’t want to give Microsoft one.

"You want to have something you do with the keyboard that is signaling to a very low level of the software -- actually hard-coded in the hardware -- that it really is bringing in the operating system you expect, instead of just a funny piece of software that puts up a screen that looks like a log-in screen, and then it listens to your password and then it’s able to do that," Gates said. "It was a mistake."

David Bradley, a designer of the original IBM PC, invented the "Control-Alt-Delete" combo.

"I may have invented it, but Bill made it famous," Bradley said.

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The command also effectively restarts the computer, but Bradley said "Why they used it for the log-in also, I don’t know."

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