What causes the error message "this program has performed an illegal operation" and what can I do about it?
This question was answered on May 7, 2003. Much of the information contained herein may have changed since posting.
The "illegal operation" error in Windows-based systems is analogous to the engine light in a car It is a general warning that your computer encountered a command or circumstance that it cannot process (similar to: does not compute).
The cause of illegal operations can range from a coding mistake (a.k.a "bug") in a program that is attempting to run, to a situation where two programs are attempting to use the same resource in your computer, such as a segment of memory.
Whenever the operating system (Windows) is presented with something that it can't process or resolve, it generates an illegal operation error message usually followed by a very technical string of information that includes a module of some sort.
This module reference is pointing out the program that caused the problem, so if you want to resolve the issue, you must figure out which program uses the module.
The best thing that the average user can do is put the exact error message (the module portion) into Google's search engine (Be sure to put " " around the error)
In most cases, you can find hundreds of web sites that will specifically address the module error and provide some information for resolving your particular error.
Remember, the 'illegal operation' portion of the error is generic; the specific information that pertains to your error follows with the module information, so search for it and not the 'illegal operation'.
'User error' is the most common cause of illegal operation error messages Whenever an older program or one that was not meant for your version of Windows gets installed (such as a printer or scanner driver), you run a very high risk of corrupting Windows.
For instance, if you purchased your printer three years ago, then bought a new computer today that had Windows XP installed on it, the disk that came with your printer will not have today’s version of the printer software If you install this disk, you will likely place very old programs files into the 'belly' of Windows, which could instantly destabilize the entire system.
You won't know that you did the damage until Windows attempts to process this old code during a specific task This could occur many days or weeks after you actually inflicted the damage.
So here are my suggestions for minimizing your chances of creating illegal operation error messages:
#1 - Always verify that you have the version of a program that is specifically designed for your version of Windows If in doubt, don’t install it!
#2 - Only install programs that you absolutely need The more stuff you install in your system, the more chances for conflict.
#3 - Always download the latest version of a driver from the manufacturers web site, instead of installing it from an included disk This is especially important with printers, scanners or any piece of hardware that will be installed inside the computer.
Most computer problems are as a result of something that was done by the user, so taking the minimalists approach will generally help you avoid problems!
About the author
Ken Colburn of Data Doctors on May 7, 2003