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MS-DOS Device Driver Names Cannot be Used as File Names
Article ID: 74496 - View products that this article applies to.
This article was previously published under Q74496
Microsoft MS-DOS reserves certain names for system device drivers. If you try to name a file using one of these names, you will receive the following error message:
The solution is to change the file name.
Write Fault Error Writing Device <FILENAME.EXT>
Abort, Retry, Ignore, Fail?
Below is a list of default device driver names.
To identify system device driver names, use one of the following two commands:
Name Function ---- -------- CON Keyboard and display PRN System list device, usually a parallel port AUX Auxiliary device, usually a serial port CLOCK$ System real-time clock NUL Bit-bucket device A:-Z: Drive letters COM1 First serial communications port LPT1 First parallel printer port LPT2 Second parallel printer port LPT3 Third parallel printer port COM2 Second serial communications port COM3 Third serial communications port COM4 Fourth serial communications port
Article ID: 74496 - Last Review: May 12, 2003 - Revision: 2.0