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james_axton

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Daylight Saving Time adjusts a file's 'Date Modified' in Vista back one hour

This is on previously existing files only.  

On these machines, 'Date Modified' happens to be important.  DST for the fall has already occurred and all older files are now timestamped as being an hour behind where they actually were.  Is there a fix for this that would display the correct timestamp on these files?  Thanks.
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bigbigpig

NTFS stores times in UTC and the operating system adjusts accordingly based on the time zone you selected.  So the timestamp on your files will move when DST occurs.
To add to that... this is from Microsoft:

Why are some time stamps and time references that are displayed in document properties affected by the DST shift?  
Programs that handle time stamps typically store those time stamps in Coordinated Universal Time (UTC). The advantage of UTC is that it is universal and invariant; it is not subject to local time zones or daylight saving time (DST). However, UTC does not display time in a format that is meaningful to most users, so computers convert UTC time to local time based on two factors: first, the time zone designated by the user, and second, whether DST is selected in the Date and Time item in Control Panel. The change in DST does not affect the historical time stamps as recorded in UTC, but the change might affect how time stamps are interpreted (and therefore displayed) by the Windows operating system and certain programs.
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ASKER

I take your response to mean that the 'Date Modified' attribute for each existing file always bounces around based on the time of year, irrespective of the OS (XP, Vista, 7).  Is that a fair assessment?
Let me know if that's the general idea and I'll close this out and award points.  Thanks.
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Thanks!