Remove Daylight Savings Time Dialog box?

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Guest

Twice a year, XP displays a dialog box telling the user that it's changed the
time due to daylight savings time.

I want to keep this dialog box from popping up, but I can't find a way to do
it.

I understand that I could turn off the automatic adjustment, and thus have
the dialog not appear. But I want the adjustment -- just not the dialog box.

So does anyone know of a mystery registry key or function to help me? I've
been throught technet & msdn etc. with no luck.

Thanks!
 
No...by design.

--
Carey Frisch
Microsoft MVP
Windows XP - Shell/User
Microsoft Newsgroups

-------------------------------------------------------------------------------------------

"imcgee" wrote:

| Twice a year, XP displays a dialog box telling the user that it's changed the
| time due to daylight savings time.
|
| I want to keep this dialog box from popping up, but I can't find a way to do
| it.
|
| I understand that I could turn off the automatic adjustment, and thus have
| the dialog not appear. But I want the adjustment -- just not the dialog box.
|
| So does anyone know of a mystery registry key or function to help me? I've
| been throught technet & msdn etc. with no luck.
|
| Thanks!
 
Twice a year, XP displays a dialog box telling the user that it's
changed the time due to daylight savings time.

I want to keep this dialog box from popping up, but I can't find a way
to do it.

I understand that I could turn off the automatic adjustment, and thus
have the dialog not appear. But I want the adjustment -- just not the
dialog box.

So does anyone know of a mystery registry key or function to help me?
I've been throught technet & msdn etc. with no luck.

Thanks!
Click to expand...

I think that you can't turn off this verification on purpose (for
important reasons such as: having the wrong time on a machine in a domain
can stop users from being able to log in).

Just to be picky - how much time have you spent (yours and others) trying
to get rid of something that takes the user about 2s to click on twice a
year? Unless you have a LOT of users, I suspect you'll never be ahead.
Although, if you are just doing it for interest, and not to actually
achieve a net savings in time, that may be a worthy enough reason.
 
HKEY_LOCAL_MACHINE\Software\Microsoft\Windows\CurrentVersion\RunOnce
Value Name: WarnTimeChanged
Data Type: REG_SZ
Value: rundll32 shell32.dll,Control_RunDLL timedate.cpl,,/m

You can manually launch this dialog box by entering the following into
Start | Run.

rundll32 shell32.dll,Control_RunDLL timedate.cpl,,/m

Date and Time Properties will open if you manually launch New Clock Settings
applet and click OK or click on the Close [X]. Just hit Cancel.

New Clock Settings
[[Windows has updated your clock as a result of Daylight Savings Time.
Please
verify that your new clock settings are correct.]]

--
Hope this helps. Let us know.

Wes
MS-MVP Windows Shell/User

In
 
Fair enough question. In the case of my application, I have a dedicated XP
box with a custom console (hardware) for user input. There is no keyboard,
no mouse, and no Enter key equivalent.

So it's less a matter of wanting to squeeze an extra 2 seconds out my users,
and more that I'd prefer not to have my application locked up twice a year.

What I *should* do is switch to xp embedded, which presumably would give me
control over this pesky window. But currently that's not a marketable
feature. ;-)
 
Thanks Wesley.

It's interesting to see the mechanism for how that window is called.

Any idea how I could short-circuit or prevent it from happening? I'd guess
that deleting timedate.cpl isn't the right way to go... ;-)

Wesley Vogel said:
HKEY_LOCAL_MACHINE\Software\Microsoft\Windows\CurrentVersion\RunOnce
Value Name: WarnTimeChanged
Data Type: REG_SZ
Value: rundll32 shell32.dll,Control_RunDLL timedate.cpl,,/m

You can manually launch this dialog box by entering the following into
Start | Run.

rundll32 shell32.dll,Control_RunDLL timedate.cpl,,/m

Date and Time Properties will open if you manually launch New Clock Settings
applet and click OK or click on the Close [X]. Just hit Cancel.

New Clock Settings
[[Windows has updated your clock as a result of Daylight Savings Time.
Please
verify that your new clock settings are correct.]]

--
Hope this helps. Let us know.

Wes
MS-MVP Windows Shell/User

In
imcgee said:
Twice a year, XP displays a dialog box telling the user that it's changed
the time due to daylight savings time.

I want to keep this dialog box from popping up, but I can't find a way to
do it.

I understand that I could turn off the automatic adjustment, and thus have
the dialog not appear. But I want the adjustment -- just not the dialog
box.

So does anyone know of a mystery registry key or function to help me?
I've been throught technet & msdn etc. with no luck.

Thanks!
Click to expand...
Click to expand...
 
That's even a more worthy reason, that I hadn't considered.

My first thought was that you could turn off the automatic adjustment for
DST, but set up the machine to set it's time from another machine (time
server) so that it still gets the correct time - but I'm not sure if this
would work correctly if the machines do not have the same timezone
setting.

My next thought was then as follows:

I think (I could be wrong) that internally the time is kept as UTC
(formerly known as GMT), and the adjustment only affects the display of
the time. In this case, maybe if you turned off the automatic
adjustment, but scheduled a task that changed the timezone when DST kicks
in or out, you would still get the correct time display. I seem to
recall seeing some commandline tool to change the timezone somewhere.

If I remember correctly, on NTFS disks, for example, the time is stored
as UTC, and when you change the timezone, the displayed time for the
files changes to match - this is why you sometimes get 1 hour shifts in
file modification time when you copy between NTFS and FAT, as FAT stores
local time instead of UTC. Or something like that.

Try changing your timezone to see what I mean - the displayed time
changes, and a directory of your files will show the same shift in time,
but the internal time on your machine hasn't been changed. I think that
if you use NET TIME from another machine to check the time on your
machine, this will be observed (as the internal time should be shown in
the time zone that the other machine is using).

Not sure if this helps, but maybe will give you some other ideas.
 
What what I've seen & read, XP is running UTC, and the timezone & daylight
adjustments are used when displaying the local time. And so, for instance,
if I have DST turned off, and I sync with a time server, I still end up off
by an hour (currently).

The problem I have with "scheduled a task that changed the timezone when DST
kicks in or out" is that I have to mimic the DST logic in order to know when
it kicks in. I'm trying to avoid doing that, as keeping up with the minutia
of DST rule changes is not something I want to burden our side with. I want
to leverage XP's knowledge.

The closest to a solution I see at this point is to write a replacement
timezone.cpl, and an installer to put it properly in \windows\system32. I
can then ignore any requests, thus freezing out the dialog box. Of course
this can't be simple, so System Restore keeps it exciting by trying to "fix"
any changes I make to timezone.cpl, but I'm sure I can figure out how to
handle this.

Thanks for the ideas!
 
Daylight Saving Time begins for most of the United States at 2 a.m. on the
first Sunday of April. Time reverts to standard time at 2 a.m. on the last
Sunday of October.

You'd have to figure out how to delete the WarnTimeChanged entry in the
RunOnce key before 2 a.m. on the first Sunday of April and before 2 a.m. on
the last Sunday of October. With a batch file probably.

I have no idea when these actually happen in Windows. But it would have to
be on the day before in order for the entry to show up at boot on that
particular Sunday.

--
Hope this helps. Let us know.

Wes
MS-MVP Windows Shell/User

In
imcgee said:
Thanks Wesley.

It's interesting to see the mechanism for how that window is called.

Any idea how I could short-circuit or prevent it from happening? I'd
guess that deleting timedate.cpl isn't the right way to go... ;-)

Wesley Vogel said:
HKEY_LOCAL_MACHINE\Software\Microsoft\Windows\CurrentVersion\RunOnce
Value Name: WarnTimeChanged
Data Type: REG_SZ
Value: rundll32 shell32.dll,Control_RunDLL timedate.cpl,,/m

You can manually launch this dialog box by entering the following into
Start | Run.

rundll32 shell32.dll,Control_RunDLL timedate.cpl,,/m

Date and Time Properties will open if you manually launch New Clock
Settings applet and click OK or click on the Close [X]. Just hit Cancel.

New Clock Settings
[[Windows has updated your clock as a result of Daylight Savings Time.
Please
verify that your new clock settings are correct.]]

--
Hope this helps. Let us know.

Wes
MS-MVP Windows Shell/User

In
imcgee said:
Twice a year, XP displays a dialog box telling the user that it's
changed the time due to daylight savings time.

I want to keep this dialog box from popping up, but I can't find a way
to do it.

I understand that I could turn off the automatic adjustment, and thus
have the dialog not appear. But I want the adjustment -- just not the
dialog box.

So does anyone know of a mystery registry key or function to help me?
I've been throught technet & msdn etc. with no luck.

Thanks!
Click to expand...
Click to expand...
Click to expand...
 
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