Illegal Operation

Updated: 10/11/2017 by Computer Hope

When the operating system or computer processor receives an instruction from a program that it does not recognize and cannot process, it may issue a command known as an Illegal Operation. Basically, it's stating the computer program is making an illegal request.

Illegal Operation

While an Illegal Operation can occur due to an instruction coming from something other than a computer program, a program issuing the illegal request is the most common cause. When this occurs, the program may close down, and any work that was unsaved is lost.

Error, Operating system terms