Fatal Exception 0E with Multiple MS-DOS Device Names in Path
Symptoms
If the last two or more components in a path match MS-DOS device names, you may receive an error message on a blue screen similar to the following example:
A fatal exception 0E has occurred at (address) in VXD (FSD) + (address). The current application will be terminated.
* Press any key to terminate the current application. * Press CTRL+ALT+DEL to restart your computer. You will lose any unsaved information in all applications.
Press any key to continue NOTE: The VXD in question is a File System Driver (FSD) from the list in the “More Information” section of this article.
If you do not restart your computer at this point, subsequent blue screen error messages occur and the computer does not shut down properly. It may be necessary to interrupt power to the computer to reset it successfully.
Alternatively, if your computer has a large amount of memory (for example, 192 MB), the mouse pointer may be displayed as an hourglass over the taskbar and you may be unable to run additional programs. The computer eventually becomes unresponsive to mouse and keyboard input.
Resolution
MS-DOS device names are reserved words and cannot be used as folder or file names. When parsing a reference to a file or folder, Windows correctly checks for the case in which a single MS-DOS device name is used in the path, and treats it as invalid. However, Windows does not check for the case in which the path includes multiple MS-DOS device names. When Windows attempts to interpret the device name as a file resource, it performs an illegal resource access operation that usually results in the computer becoming unresponsive.
Because you cannot create files or folders that contain MS-DOS device names, it is unusual for a user to try to gain access to one under normal circumstances. The chief threat posed by this vulnerability is that a malicious user can entice a user to attempt such an access. For example, if a Web site operator hosts a hyperlink that references such a path, when the user clicks the link, the computer may hang. Likewise, a Web page or HTML e-mail message that specifies a local file as the source of rendering information can cause the user’s computer to hang when it is displayed. If this happens, you can put the computer back into normal service by restarting it.