Why You Can't Name A File CON In Windows
Tom ScottCited 4× on HN, 2020–2026
explainer · general · evergreen · 2020–2026 on HN
Tom Scott explains why Windows does not let you name a file CON, tracing the reserved device names back to backwards compatibility with DOS.
Linked as a relevant explainer in threads about Windows quirks and reserved names.
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4 comments from Hacker News
Don't think this will ever happen, especially since this is Microsoft you are talking about [0] [0] ▶ this video
It's wild to me some of the things I never knew, even though I've been using Windows or DOS for probably 35 years. For example, I recently learned you can't name a file CON. Try it. Somehow over all those decades, I've never tried to do this until Tom Scott made a video about it: ▶ this video
can't speak about the very recent updates, but windows have been consistent and adamant on keeping the backward compatibility. they still use reserved file names for io devices so that 30+ year old printers can still work, and you can still open a 2000s doc file in office 365. (I'm looking at you Apple, who made many of the 32 bit apps I loved useless) relevant video: ▶ this video (Tom Scott: Why you can't use CON as filename in windows)
Excel also has a deliberate bug where it thinks 1900 is a leap year because they wanted compatibility with Lotus 123, where the bug was actually a bug! [0] [0] ▶ this video