OL98: SetColumns Returns Incorrect Times When Used with Tasks

ID: Q219034

The information in this article applies to:

Microsoft Outlook 98

SYMPTOMS

When using the SetColumns method to retrieve dates or times from tasks, the times may not accurately reflect what is stored in the task.

CAUSE

With the exception of tasks, all dates in Outlook are stored in Coordinated Universal Time (UTC), also known as Greenwich Mean Time (GMT). However, tasks store dates in local time. The SetColumns method always converts the retrieved time into local time, therefore causing the times to be offset.

WORKAROUND

Method 1: Do Not Use SetColumns

Do not use the SetColumns method to retrieve dates with tasks. In most cases this will adversely affect your solution's performance.

Method 2: Retrieve and Use an OffSet

NOTE: If you are using Visual Basic Scripting Edition (VBScript), you cannot access the system registry and this workaround does not apply.

If you are using Visual Basic or Visual Basic for Applications, programmatically get the local time zone information from the computer running your application. This information is stored in the following location in the registry:

HKEY_Local_Machine\SYSTEM\CurrentControlSet\Control\TimeZoneInformation

The Bias value specifies the current bias, in minutes, for local time translation on the computer. The bias is the difference, in minutes, between local time and UTC. Use this value to correct the time retrieved using the SetColumns method.

STATUS

Microsoft has confirmed this to be a bug in the Microsoft products listed at the beginning of this article.

MORE INFORMATION

The Date type is implemented as a floating-point value, measuring days from midnight, December, 30 1899. To interpret the time portion, take the absolute value of the fractional part of the number. Since the bias is measured in minutes however, you must divide the bias by the number of minutes in a day (1440) in order to perform the conversion. The formula is:


   local time + (Bias / 1440 ) = UTC

For example, the Date value of a task to be started February 14, 1999 (UTC) should be 36205.0. However, if your application is run on a computer in New York, the Date value (local time) will be 36204.7916667 (February 13, 1999 7:00 P.M.). To perform the conversion, find the computer's bias (from the registry), which is 0x0000012c (300 minutes). Using this in the formula, we have:


   local time + (Bias / 1440 ) = UTC
   36204.7916667 + (300/1440) = 36205.0
   (February 13, 1999 7:00 PM + 5hrs) = February 14, 1999 0:00am

For more information about using Visual Basic to retrieve values from the registry, please see the following article in the Microsoft Knowledge Base:

Q1456796 HOWTO: Use the Registry API to Save and Retrieve Setting

Steps to Reproduce the Problem:

Microsoft provides programming examples for illustration only, without warranty either expressed or implied, including, but not limited to, the implied warranties of merchantability and/or fitness for a particular purpose. This article assumes that you are familiar with the programming language being demonstrated and the tools used to create and debug procedures. Microsoft support professionals can help explain the functionality of a particular procedure, but they will not modify these examples to provide added functionality or construct procedures to meet your specific needs. If you have limited programming experience, you may want to contact the Microsoft fee-based consulting line at (800) 936-5200. For more information about the support options available from Microsoft, please see the following page on the World Wide Web:

http://www.microsoft.com/support/supportnet/refguide/

Create a new task in the default tasks folder.

Set the Subject to New Task.

Set the Start date to any date and time.

Save the task.

Enter the following automation code into Visual Basic or Visual Basic for Applications:


Private Sub Command1_Click()
   Dim OutApp As Outlook.Application
   Dim oNameSpace As Outlook.NameSpace
   Dim oFolder As Outlook.MAPIFolder
   Dim oItems As Outlook.Items
   Dim oTask As Outlook.TaskItem

   Set OutApp = New Outlook.Application
   Set oNameSpace = OutApp.GetNamespace("MAPI")
   Set oFolder = oNameSpace.GetDefaultFolder(olFolderTasks)
   Set oItems = oFolder.Items

   Set oTask = oItems("New Task")
   MsgBox CDbl(oTask.StartDate)

   oItems.SetColumns "StartDate"
   Set oTask2 = oItems("New Task")
   MsgBox CDbl(oTask2.StartDate)
End Sub

Add a reference to the Microsoft Outlook 98 Object Model.

Run the code.

REFERENCES

For more information about creating solutions with Microsoft Outlook 98, please see the following articles in the Microsoft Knowledge Base:

Q180826 OL98: Resources for Custom Forms and Programming

Q182349 OL98: Questions About Custom Forms and Outlook Solutions

Additional query words: OutSol OutSol98 vbscript


Keywords          : kbdta OffVBS 
Version           : WINDOWS:
Platform          : WINDOWS 
Issue type        : kbbug

Last Reviewed: April 6, 1999