Plea to Microsoft to allow RTC=UTC

Markus Kuhn Markus.Kuhn at
Mon Jul 2 16:05:47 UTC 2001

I have managed to get someone inside Microsoft interested in the
problems of the old MS-DOS convention of keeping the RTC in some local
time that is not further specified in the CMOS RAM data. I was asked to
write up a case to convince Microsoft management to dedicate resources
for fixing this and enabling the Windows RTC driver to maintain the
battery clock in Universal Time instead of local time.

I just did so on

and I would like to invite all computer time gurus out there to review
this brief essay before I send it off to Redmond.

Please let me know if you have any further

 - arguments
 - technical suggestions/proposals
 - related references
 - URLs of well-documented RTC DST problem stories

that you think that whoever at Microsoft touches the Windows RTC code
next should be aware of.



Markus G. Kuhn, Computer Laboratory, University of Cambridge, UK
Email: mkuhn at,  WWW: <>

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