Friday, March 28, 2008

Daylight Savings Mayhem - Automating a Check of Notes INI

Yesterday we discovered that there are changes to the Australian Daylight Savings dates coming into effect this weekend (it will continue when it would normally have ended).

There are lots of repercussions, but the worst (ones that could affect the business) relate to the Lotus Notes Calendar.

There are two things to do to prepare ourselves;
  • Windows Updates on our clients (WinXP)
  • Windows Updates on our servers (Win2003)

We can handle the servers ourselves but how do we know if the clients have done their updates? Simple, we ask them by sending a button around so they can determine the answers for themselves.

Creating a Button that can be mailed to Notes Users
Here's the LotusScript code on my button;

Sub Click(Source As Button)
  Dim vDSTText As Variant
  Dim Session As New NotesSession

  Const CorrectDST = "10,1,1,4,1,1"
  vDSTText = Session.GetEnvironmentString("DSTLAW",1)
  If vDSTText = CorrectDST Then
     Msgbox "Your Time Settings are Correct!", 64, "Checking Time Settings"
     Msgbox "Your Time Settings are NOT Correct! - You need to do a Windows Update", 48, "Checking Time Settings"
  End If
End Sub

Basically, all we're doing is having a look at the value next to DSTLAW in the Notes.ini file.
In our case, it says... 10,1,1,4,1,1

Syntax: DSTlaw=begin_month, begin_week, begin_day, end_month, end_week, end_day

Which means Daylight Savings - BEGIN October, Week 1, Day 1 and END April, Week 1, Day 1

You could easily change the Const CorrectDST = "10,1,1,4,1,1" value to cater for different locations.

Note: Although you can write back to the Notes.INI file, don't be tempted to do this. The value is set when Notes starts from the Operating System, so making changes at this level won't fix anything.


crodrig5 said...

Hi Gavin,
is it "END March, Week 1, Day 1" or "END April, Week 1, Day 1"

Also the 3rd and 6th parameters I think refer to the 1st Sunday rather than the 1st of the month. This site explains it well:


Gavin Bollard said...

Thanks crodrig5, Well spotted. I wrote the explanations off the cuff and obviously wasn't concentrating. It's end April.

Michelle said...

Gavin - are you aware that NSW, VIC and I think TAS have also changed the start date for DST from the last Sunday in October to the first?

Anyone in these Australian states who has to make changes for this weekend should pro-actively check for the next change as well.

The earlier you make the changes, the fewer problems you will experience

Michelle said...

Gavin - you should be aware that the start of DST for 2008 has also moved - from the last weekend in October to the first weekend.

Now is a good time for all Domino Admins in NSW and VIC to check that this boundary is also correct.