One of my favorite (and free!) little utilities is DocMessageClass as it makes it easy to change the message class on existing items to use a new published form. Unfortunately, it doesn't work with 64-bit versions of Outlook (which is the default install for new computers.) If you have 32-bit Office installed, you can use DocMessageClass.

Although not quite as easy to use as DocMessageClass, you can use a macro or PowerShell script to change the message class in all versions, including Outlook 2013 and newer.

Note: these methods work for any Outlook item, not just contacts.

Using PowerShell to change the message class

You can use PowerShell to change the message class. The first example changes the message class of all Contact items, while the second one changes a specific message class.

# Change the message class of all contacts
$olApp = new-object -comobject outlook.application
$namespace = $olApp.GetNamespace("MAPI")

# Default Contacts folder
$Contacts = $namespace.GetDefaultFolder(10)

foreach ($Contact in $Contacts.Items)
{

# Don't change distribution lists
    if ($Contact.messageclass -notlike "*distlist*")
    {
              
   $Contact.messageclass  = "IPM.Contact.form-name"  
   $Contact.Save()

    }
}

$olApp.Quit | Out-Null
[GC]::Collect()

Change specific message classes

Use this macro to change specific message classes to another message class.

# Change the message class of all contacts
$olApp = new-object -comobject outlook.application
$namespace = $olApp.GetNamespace("MAPI")

# Default Contacts folder
$Contacts = $namespace.GetDefaultFolder(10)

foreach ($Contact in $Contacts.Items)
{

# Don't change distribution lists, change specific class
    if ($Contact.messageclass -notlike "*distlist*" -or $Contact.messageclass -like "*new*")
    {
  
   $Contact.messageclass  = "IPM.Contact.form-name"  
   $Contact.Save()

    }
}

$olApp.Quit | Out-Null
[GC]::Collect()

Run on a non-default folder

This code sample is from Kenny in our forum.
can't get custom form to update multiple contacts using VBA

To use, enter the name of the folder in the code. The folder does not need to be selected before running the PowerShell.

# Change the message class of all contacts
$olApp = new-object -comobject outlook.application
$namespace = $olApp.GetNamespace("MAPI")
$Contacts = $namespace.GetDefaultFolder(10)
# Specify target folder
$myNewFolder = $Contacts.Folders("subfolder name")

foreach ($Contact in $myNewFolder.Items)
{
# Don't change distribution lists
if ($Contact.messageclass -notlike "*distlist*")
{
# specify new message subclass
$Contact.messageclass = "IPM.Contact.custom-form-name"
$Contact.Save()
}
}
$olApp.Quit | Out-Null
[GC]::Collect()

Change the message class of the selected folder

This version of the PowerShell works with the selected folder. Select a folder then run the macro.

# Change the message class of all contacts
$olApp = new-object -comobject outlook.application
$Contacts = ($olApp.ActiveExplorer()).CurrentFolder

Write-Host "Current folder is $Contacts"
foreach ($Contact in $Contacts.Items) {
# Don't change distribution lists
if ($Contact.messageclass -notlike "*distlist*")
{
# Specify new message subclass
$Contact.messageclass = "IPM.Contact.custom-form-name"
$Contact.Save()
}
}
$olApp.Quit | Out-Null
[GC]::Collect()

Change message class on selected items

This PowerShell will change the message class on the select items.

# Change the message class of all contacts
$olApp = new-object -comobject outlook.application
$namespace = $olApp.GetNamespace("MAPI")

$currentExplorer = ($olApp.ActiveExplorer())
$Selection = $currentExplorer.Selection

write-host $selection.count

foreach ($Contact in $Selection)
{
# Don't change distribution lists
if ($Contact.messageclass -notlike "*distlist*")
{
# specify new message subclass
$Contact.messageclass = "IPM.Contact"
$Contact.Save()
}
}
$olApp.Quit | Out-Null
[GC]::Collec

Using PowerShell Scripts

To use, right-click on the Start menu in Windows 10 and click on the Windows PowerShell entry. Paste the entire script in the PowerShell window and press Enter.

If you want to save the script as a .ps1 file, paste it into Notepad and save it with the extension .ps1. To open it in the PowerShell IDE, type powershell on the start menu and click on Windows PowerShell IDE when the PowerShell app is found. Paste the script in the editing window.

To use it, you need to allow local scripts by running this command:

Set-ExecutionPolicy RemoteSigned

Using VBA to change the message class

This first macro is based off of a macro provided by Microsoft, intended to be used in a template (see the KB article for details if you want to run it from a template.

Sub ChangeContactMessageClass()
 
  ' Change the following line to your new Message Class
   NewMC = "IPM.Contact.Test"
 
   Set CurFolder = Application.ActiveExplorer.CurrentFolder
   Set AllItems = CurFolder.Items
   NumItems = CurFolder.Items.count
 
   ' Loop through all of the items in the folder
   For i = 1 To NumItems
 
      Set CurItem = AllItems.Item(i)
       
' Test for a distlist
 If CurItem.Class = olContact Then
  
      ' Test to see if the Message Class needs to be changed
      If CurItem.MessageClass <> NewMC Then
 
         ' Change the Message Class
         CurItem.MessageClass = NewMC
 
         ' Save the changed item
         CurItem.Save
 
      End If
 End If
   Next
 
   MsgBox "Done."
 
End Sub

Macro alternative to DocMessageClass

This alternative to DocMessageClass was posted by chaplaindoug in Outlook Forums: How to Set Existing Contacts to Custom Form

This macro shows how to use change the message class of Public Folder contacts.

Sub ChangeMessageClass()
UName = Environ("UserName")
Set olNS = Application.GetNamespace("MAPI")
Set ContactsFolder = olNS.Folders("Public Folders - " + UName + "@goodnewsjail.org")
Set ContactsFolder = ContactsFolder.Folders("All Public Folders")
Set ContactsFolder = ContactsFolder.Folders("Good News Contacts")

'to use on the default contacts folder instead, uncomment this line
'Set ContactsFolder = olNS.GetDefaultFolder(olFolderContacts)

Set ContactItems = ContactsFolder.Items

For Each itm In ContactItems

If itm.MessageClass = "IPM.Contact" Then
itm.MessageClass = "IPM.Contact.Good News Contact"
itm.Save
End If

Next
End Sub

Change message class as item is saved

If you need to change the message class on some items, you can use an ItemAdd macro to change the message class when the new item is saved.

This could be used with an If statement to change the message class according to a value in a field (for example, If item.country = "Canada"), or when a new item is created in such a way that the custom form is not used.

Option Explicit
Private WithEvents newContacts As Outlook.Items
  
Private Sub Application_Startup()
 Set newContacts = Session.GetDefaultFolder(olFolderContacts).Items
End Sub

Private Sub newContacts_ItemAdd(ByVal Item As Object)
If Item.Class = "IPM.Distlist" Then Exit Sub

 Dim NewMC As String
NewMC = "IPM.Contact.MapIt"
    
 If Item.Class = olContact Then
      If Item.MessageClass <> NewMC Then
         Item.MessageClass = NewMC
         Item.Save
      End If
 End If

End Sub

Change the message class when a contact is edited

This macro changes the message class when you edit and save a contact.

Public WithEvents cItems As Outlook.Items

Public Sub Initialize_handler()
    Set cItems = Application.ActiveExplorer.CurrentFolder.Items 
End Sub

Sub cItems_ItemChange(ByVal Item As Object)
 
  ' Change the following line to your new Message Class
   NewMC = "IPM.Contact.robert-form"
   
 If Item.Class = olContact Then
      If Item.MessageClass <> NewMC Then
         Item.MessageClass = NewMC
         Item.Save
      End If
 End If
  
End Sub

How to use the Macro

First: You will need macro security set to low during testing.

To check your macro security in Outlook 2010 and newer, go to File, Options, Trust Center and open Trust Center Settings, and change the Macro Settings. In Outlook 2007 and older, it’s at Tools, Macro Security. If Outlook tells you it needs to be restarted, close and reopen Outlook. Note: after you test the macro and see that it works, you can either leave macro security set to low or sign the macro.

Now open the VBA Editor by pressing Alt+F11 on your keyboard.

To put the code in a module:

1. Right click on Project1 and choose Insert > Module
2. Copy and paste the macro into the new module.

More information as well as screenshots are at How to use the VBA Editor.