On further reflection the following may work, though I am not sure of the effect of changing the subject on the message history.
Option Explicit
Sub CreateReplyFromTemplate()
Dim olInsp As Outlook.Inspector
Dim olRepInsp As Outlook.Inspector
Dim wdDoc As Object
Dim wdDoc2 As Object
Dim oRng As Object
Dim oSource As Object
Dim oBM As Object
Dim olItem As Outlook.MailItem
Dim olItemReply As Outlook.MailItem
Dim olTempItem As Outlook.MailItem
Dim sTemplate As String
sTemplate = Environ("AppData") & "\Microsoft\Templates\Map.oft"
On Error Resume Next
Set olItem = ActiveExplorer.Selection.Item(1)
Set olItemReply = olItem.Reply
Set olTempItem = Application.CreateItemFromTemplate(sTemplate)
With olTempItem
.BodyFormat = olFormatHTML
Set olInsp = .GetInspector
Set wdDoc = olInsp.WordEditor
Set oBM = wdDoc.Bookmarks("_MailAutoSig")
If Not oBM Is Nothing Then
oBM.Range.Delete
End If
Set oSource = wdDoc.Range
End With
With olItemReply
.BodyFormat = olFormatHTML
.subject = "Please Complete Template - " & .subject
Set olRepInsp = .GetInspector
Set wdDoc2 = olRepInsp.WordEditor
Set oRng = wdDoc2.Range(0, 0)
.Display 'This line is required
oRng.formattedtext = oSource.formattedtext
'.Send 'Remove the apostrophe from the start of this line after testing
End With
olTempItem.Close olDiscard
lbl_Exit:
Set olItemReply = Nothing
Set olItem = Nothing
Set olTempItem = Nothing
Set olInsp = Nothing
Set wdDoc = Nothing
Set oRng = Nothing
Set oBM = Nothing
Exit Sub
End Sub