Updating contact groups in Outlook from an Excel file

I have a sheet in an Excel file with names and email addresses.

I what to go through the sheet and update the Outlook group contacts that corresponds to the headers.

Sub CreateOutlookContactGroups()
    
    Dim olApp As Object
    Dim olNS As Object
    Dim olContacts As Object
    Dim olDistList As Object
    Dim olRecip As Object
    Dim lastRow As Long
    Dim i As Long
    
    'Get Outlook application object
    Set olApp = CreateObject("Outlook.Application")
    Set olNS = olApp.GetNamespace("MAPI")
    Set olContacts = olNS.GetDefaultFolder(10) '10 = olFolderContacts
    
    'Get last row of email addresses
    lastRow = Cells(Rows.Count, "X").End(xlUp).Row
    
    'Loop through each column from E to L in row 4
    For i = 5 To 12 'Columns E to L
        If Range(Cells(4, i), Cells(4, i)).Value <> "" Then 'Check if there is a value in cell
            'Create or Get existing distribution list
            On Error Resume Next
                Set olDistList = olContacts.Items("IPM.DistList." & Range(Cells(4, i), Cells(4, i)).Value)
                If olDistList Is Nothing Then 'Create new distribution list
                    Set olDistList = olContacts.Items.Add("IPM.DistList")
                    olDistList.Save
                    olDistList.Subject = Range(Cells(4, i), Cells(4, i)).Value
                End If
            On Error GoTo 0
            
            'Add each email address from column X to distribution list if there is an "X" in the corresponding cell
            For j = 6 To lastRow 'Row 6 to last row with email addresses
                If Range(Cells(j, i), Cells(j, i)).Value = "X" Then 'Check if there is an "X" in cell
                    Set olRecip = olDistList.AddMember(CStr(Range(Cells(j, "X"), Cells(j, "X")).Value))
                    olDistList.Save
                End If
            Next j
        End If
    Next i
    
    'Release Outlook objects
    Set olRecip = Nothing
    Set olDistList = Nothing
    Set olContacts = Nothing
    Set olNS = Nothing
    Set olApp = Nothing
    
    MsgBox "Kontakt grupper uppdaterrade!"   
End Sub

The code stops running at

Set olRecip = olDistList.AddMember(CStr(Range(Cells(j, "X"), Cells(j, "X")).Value))

and throws a incompatible types fault, but the value is a valid email address.

Solution

The DistListItem.AddMember method accepts an instance of the Recipient class to be added to the list. You can use the NameSpace.CreateRecipient method which creates a Recipient object. The name of the recipient can be a string representing the display name, the alias, or the full SMTP email address of the recipient. For example:

Sub AddNewMember() 
 'Adds a member to a new distribution list 
 Dim objItem As Outlook.DistListItem 
 Dim objMail As Outlook.MailItem 
 Dim objRcpnt As Outlook.Recipient 
 
 Set objMail = Application.CreateItem(olMailItem) 
 Set objItem = Application.CreateItem(olDistributionListItem) 
 'Create recipient for distlist 
 Set objRcpnt = Application.Session.CreateRecipient("Eugene Astafiev") // or your email address
 objRcpnt.Resolve 
 objItem.AddMember objRcpnt 
 'Add note to list and display 
 objItem.DLName = "Northwest Sales Manager" 
 objItem.Body = "Regional Sales Manager - NorthWest" 
 objItem.Save 
 objItem.Display 
End Sub