Maximum Number of LPT and COM Ports

Last reviewed: May 6, 1997
Article ID: Q100111

The following information applies to:

Microsoft Windows NT operating system version 3.1

The maximum number of COM and LPT ports that Windows NT supports is 256. This is a limitation in Control Panel and does not represent a limitation of the hardware platform. In both Intel x86 and MIPS machines, the number of COM and LPT ports is only limited by available interrupts, I/O addresses and, ultimately, 4,294,967,295 (32 bits).

Additional query words: prodnt
Keywords : kbother ntgeneral
Version : 3.1
Platform : WINDOWS

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Last reviewed: May 6, 1997
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