SRS - slight delay. I had to look this one up again.

Microsoft Windows XP Embedded: Data Execution Prevention from the Microsoft Developers Network Library, doesn't give much more than a definition, but has links to how you can "embed" the feature into programs you write. What's significant at this point is that it does offer the alternate terminology "NX" – for non-execute. The feature can be done in software if you don't have an enabled processor. This may be the one you already quoted?

The article appears under MSDN "Best Practices for Security," subtopic "Local Security Considerations."

The error is unlikely to be coming from Win Explorer, but another process – probably from an installed program – can cause an error in a "Windows essential process" like WinExplorer. If you are only doing file transfers, and don't have another program active, it's most likely to be caused by something that loads out of Start or Startup. It could possibly be caused by an AV or AS program, or a cookie blocker that isn't aware of the "new" malloc (pardon - memory allocation) requirements for systems using NX.

If you're doing massive transfers it's possible that your computer is trying to use NX memory pages for temps, and hits a clinker when an executable file is copied into a disallowed part of memory. I don't have enough info to tell whether just copying an executable without opening it is a possible trigger. Some AV programs attempt to scan any files that you move, particularly if the move is from one drive to another.

Data Execution Prevention is another MSDN article that gives more of a basic "theory of DEP/NX," but probably isn't too helpful to anyone not writing code.

It shouldn't take a lot of "code smarts" to see why older programs can run into problems with this system, from what's in this last article; but it's not something you really need to know to work the fix. When you find out what program is causing the problem, this might be the one to refer the builder to when he says he doesn't know what you're talking about.

CHECK THIS ONE:

You receive a "Data Execution Prevention" error message in Windows XP Service Pack 2 or in Windows XP Tablet PC Edition 2005 is a little more helpful. It gives a step-by-step procedure for a workaround, but says you really should "contact the program builder for an update."

This last article gives some info on what you can do and what you can't in each of the DEP modes. My guess is that you haven't found/gotten to the right mode to apply the setting you want, or you haven't identified the right program to add to the exceptions list. Unfortunately, if you have, or if you do, get into the right mode, you probably still will have to figure out what program/process is the trigger in order to work around it. It's fairly safe to bet that Windows Explorer is NOT the process that causes the problem. WinExp just dies because something else ate part of its brain.

If you can't identify the program that's causing the error message, about the only way I can think of for finding it would be to uninstall suspects one at a time and see if the problem goes away. There probably is a better way, but …

You receive a Stop error when a driver is not compatible with the Data Execution Prevention (DEP) feature in Windows XP Service Pack 2 or in Windows XP Tablet PC Edition 2005 offers another source for DEP error – a driver – but the error message looks different than what you've described. This article does tell you how you can turn off DEP/NX protection completely; but you should consider that a "last resort."

You cannot install Paint Shop Pro 8 in Windows XP Service Pack 2 or in Windows XP Tablet PC Edition 2005 indicates that PSP8 is not compatible with DEP. If that's one of the programs you have installed, it goes high on the suspect list. Note that "you cannot install" means that the installation fails, not necessarily that the program can't run. There is a workaround using a modified install method for this program. "Installers" generally seem to have problems here.

Programs that are known to experience a loss of functionality when they run on a Windows XP Service Pack 2-based computer gives some specific programs, and links to some others and/or fixes. Note that this list includes programs that may fail for reasons other than DEP. Also note that there are several AV programs on the list, and several programs whose Installers and UnInstallers fail.

More Background:

A detailed description of the Data Execution Prevention (DEP) feature in Windows XP Service Pack 2 and Windows XP Tablet PC Edition 2005. This gives a less-geek explanation. Consider it "nice to know later" for now. I don't think it gives any specific solutions, but some of our more nerdy folk may be interested in a quick look to see what's being talked up.

John