Daylight Savings Time Problem


G

Guest

The automatic Daylight Savings Time clock adjustment feature also changes my
file dates/times.

How do I force Microsoft leave the file dates alone?

A file date may be listed as 3/20/2007, 10:30am, and once DST shifts, it
changes to 3/20/2007, 11:30am.

I back-up my files using a third-party software that among other things
looks at the latest file date to prepare back-ups to a separate hard drive.
When the computer automatically updates the clock to daylight savings time,
the file comparison shows that all of my files are now listed with a
modification date that is exactly one-hour newer than that of the last
back-up files. The back-up now wants to replace every file with the “newerâ€
version. Since I have many files, this is not a reasonable approach.

If I perform the update, and replace the “old†files, this creates a similar
problem when DST reverts to standard time. Since I am essentially mirroring
the files, twice per year I have to do this ridiculous change.

As a side note, this same effect also applies when I shift time zones – e.g.
visiting a different location. However, in that case, Microsoft also screws
up all of my Outlook calendar entries for any event scheduled as an “all-dayâ€
event and changes them to a 24 hour event starting one evening and ending the
next.
 
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H

HEMI-Powered

Today, =?Utf-8?B?Sm9obiBHcmVnb3J5?= made these interesting
comments ...
The automatic Daylight Savings Time clock adjustment feature
also changes my file dates/times.

Huh? Windows cannot change the date stamp of files already
created or modified but will obviously update them to the then-
current date and time IF you modify what is already on your HD.
For starters, until you're sure of what you are doing, perhaps
you should create a new file name?
 
R

Rock

John Gregory said:
The automatic Daylight Savings Time clock adjustment feature also changes
my
file dates/times.

How do I force Microsoft leave the file dates alone?

A file date may be listed as 3/20/2007, 10:30am, and once DST shifts, it
changes to 3/20/2007, 11:30am.

I back-up my files using a third-party software that among other things
looks at the latest file date to prepare back-ups to a separate hard
drive.
When the computer automatically updates the clock to daylight savings
time,
the file comparison shows that all of my files are now listed with a
modification date that is exactly one-hour newer than that of the last
back-up files. The back-up now wants to replace every file with the
“newerâ€
version. Since I have many files, this is not a reasonable approach.

If I perform the update, and replace the “old†files, this creates a
similar
problem when DST reverts to standard time. Since I am essentially
mirroring
the files, twice per year I have to do this ridiculous change.

As a side note, this same effect also applies when I shift time zones –
e.g.
visiting a different location. However, in that case, Microsoft also
screws
up all of my Outlook calendar entries for any event scheduled as an
“all-dayâ€
event and changes them to a 24 hour event starting one evening and ending
the
next.


Yes, that is an effect if the file system is NTFS. It doesn't change with
FAT32. Nothing you can do about it, AFAIK.
 
R

Rock

HEMI-Powered said:
Huh? Windows cannot change the date stamp of files already
created or modified but will obviously update them to the then-
current date and time IF you modify what is already on your HD.
For starters, until you're sure of what you are doing, perhaps
you should create a new file name?

Actually it does. If the file system is NTFS, the time stamp is changed to
refect the DST time change.
 
H

HEMI-Powered

Today, Rock made these interesting comments ...
Actually it does. If the file system is NTFS, the time stamp
is changed to refect the DST time change.

How the Hell can ANY O/S update the date/time stamp on ANY
existing file(s)???!!! I guess I have to believe it, but this
makes NO sense to me whatsover. Creation date and time are that.
Last modification date and time are that. It is ONLY the clock
that updates up or down with DST whether it be the old kind or
the 2007 kind. Please tell me this is NOT a "feature"!
 
E

Eric

HEMI-Powered said:
Today, Rock made these interesting comments ...


How the Hell can ANY O/S update the date/time stamp on ANY
existing file(s)???!!! I guess I have to believe it, but this
makes NO sense to me whatsover. Creation date and time are that.
Last modification date and time are that. It is ONLY the clock
that updates up or down with DST whether it be the old kind or
the 2007 kind. Please tell me this is NOT a "feature"!
I agree. I hadn't even noticed it did that but it makes no sense. I have
files on my computer that say last modified about 5:30PM, on a computer that
is never used past 5PM. If you create a file at 1:59, then change your
clock at 2 to spring forward an hour, the next file you create should say it
was created an hour later. It doesn't really make sense to say that first
file was created at 2:59 because it wasn't. That is an undocumented "stupid
feature" that would more likely mess people up.
 
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G

Guest

Well, if I have to live with this bizare time change problem, is there a way
I can tell my back-up drive that DST has changed?

The basic idea is that I do not want to spend the several hours to re-write
every file on my back-up drive (external/USB) twice per year when a routine
synchronization only lasts about 5 minutes.
 
L

Lem

Eric said:
I agree. I hadn't even noticed it did that but it makes no sense. I have
files on my computer that say last modified about 5:30PM, on a computer that
is never used past 5PM. If you create a file at 1:59, then change your
clock at 2 to spring forward an hour, the next file you create should say it
was created an hour later. It doesn't really make sense to say that first
file was created at 2:59 because it wasn't. That is an undocumented "stupid
feature" that would more likely mess people up.

As I understand it, the date/time stamp is kept in UTC. The "stamp"
isn't changed, but it is reported differently.

Thus, in Eric's example, if he created a file at 4:30 pm (1630) EST, the
file stamp would be (internally) 2130 (9:30pm) UTC (aka GMT). And if
you looked at that stamp after the computer's time zone had changed from
-5 to -4 (either because you moved from New York to Bermuda or because
you stayed in NY and changed to Daylight Saving Time), it would show as
5:30pm.

The reason it's confusing is because the date/time stamp on the file's
properties doesn't specify what time zone it is reporting (the designer
probably assumed that the computer user ought to know what time zone
he's in).
 
H

HEMI-Powered

Today, Eric made these interesting comments ...
I agree. I hadn't even noticed it did that but it makes no
sense. I have files on my computer that say last modified
about 5:30PM, on a computer that is never used past 5PM. If
you create a file at 1:59, then change your clock at 2 to
spring forward an hour, the next file you create should say it
was created an hour later. It doesn't really make sense to
say that first file was created at 2:59 because it wasn't.
That is an undocumented "stupid feature" that would more
likely mess people up.

It has been said, Eric, that if a program does what the
programmer intended it to do, even if users do NOT like it, it is
a feature, but if it does NOT do what the programmer wants even
when users DO want it, it is a bug!

I guess in retrospect, I really don't care if XP did or didn't
mod any of my files, I didn't notice it, but so what? <grin>
 
G

Guest

OK, that being said, how do I tell me back-up drive that the time has shifted
by one hour? The back-up drive does not seem to be influenced by Windows,
but it does report the timestamp one hour off.

Just out of curiosity, why would the local hard drive be affected by the
time change, but not the back-up drive if the file timestamp has not really
changed? Why does Windows report the time two differnt ways?
 
R

Rock

John Gregory said:
Well, if I have to live with this bizare time change problem, is there a
way
I can tell my back-up drive that DST has changed?

The basic idea is that I do not want to spend the several hours to
re-write
every file on my back-up drive (external/USB) twice per year when a
routine
synchronization only lasts about 5 minutes.

I don't know. Why not just run it overnight or when you're not going to be
using the computer? I use drive imaging to image the drives nightly, so
this issue doesn't affect me.
 
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G

Guest

Rock said:
I don't know. Why not just run it overnight or when you're not going to be
using the computer? I use drive imaging to image the drives nightly, so
this issue doesn't affect me.

Rock,

Your work around will allow me to continue, however, I am curious why the
files on the internal hard drive are changed, but the files on the external
hard drive are not changed?

I have tried re-starting the computer with bthe external drive attached,
changing the time, DST, and time zone settings with the drive both attached
and detached, all with no effect. To Windows, what makes the difference
between the internal and external drives?
 
B

Bob I

John said:
:




Rock,

Your work around will allow me to continue, however, I am curious why the
files on the internal hard drive are changed, but the files on the external
hard drive are not changed?

I have tried re-starting the computer with bthe external drive attached,
changing the time, DST, and time zone settings with the drive both attached
and detached, all with no effect. To Windows, what makes the difference
between the internal and external drives?

Time stamp changes with daylight savings
http://support.microsoft.com/kb/129574/en-us


perhaps you are using FAT32 on the external drive?
 
A

Asher_N

Today, Rock made these interesting comments ...


How the Hell can ANY O/S update the date/time stamp on ANY
existing file(s)???!!! I guess I have to believe it, but this
makes NO sense to me whatsover. Creation date and time are that.
Last modification date and time are that. It is ONLY the clock
that updates up or down with DST whether it be the old kind or
the 2007 kind. Please tell me this is NOT a "feature"!

Stop thinking small. It's a feature. The time stamp is kept in UTC, it is
converted to local for display purposes. If you have to sync multiple
systems across time zones, you will learn to love that feature.
 
A

Asher_N

Today, Eric made these interesting comments ...


It has been said, Eric, that if a program does what the
programmer intended it to do, even if users do NOT like it, it is
a feature, but if it does NOT do what the programmer wants even
when users DO want it, it is a bug!

I guess in retrospect, I really don't care if XP did or didn't
mod any of my files, I didn't notice it, but so what? <grin>

A feature is a bug with seniority.
 
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L

Linda Edmondson

This is a terrible problem. There should be a way to turn this feature
(horror) off. PLEASE LEAVE MY APPOINTMENTS ALONE. I don't switch time
zones. Various glitches have destroyed my appointmens with this feature
twice. Now I don't trust them anymore. Do I have to keep them on paper now
that Windows is playing games with them?
 
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