Option Explicit

' CC BY-SA
' by Gee Law on github.com/geelaw

Sub DetachTemplate()
'
' DetachTemplate Macro
'
'
    If ActiveDocument.AttachedTemplate = NormalTemplate Then

        MsgBox "The document is already attached to the normal template.", vbInformation, "Already attached"
        Exit Sub

    End If

    If MsgBox("Do you want to attach the normal template to this document?", vbQuestion + vbYesNo + vbDefaultButton2, "Detaching custom template") = vbYes Then

        On Error GoTo NotAnExpectedAction
        ActiveDocument.Styles.Item ("Detach Template Tip")

        On Error GoTo AttachTemplateFailed
        ActiveDocument.AttachedTemplate = NormalTemplate

        On Error GoTo CleanupFailed
        With ActiveDocument.Content.Find
            .Style = "Detach Template Tip"
            .Wrap = wdFindContinue
            With .Replacement
                .Text = ""
            End With
            .Execute Replace:=wdReplaceAll
        End With
        ActiveDocument.Styles("Detach Template Tip").Delete

        MsgBox "Successfully attached the normal template to this document.", vbInformation, "Successful operation"

        Exit Sub

NotAnExpectedAction:
        MsgBox "This file is not supported." & vbCrLf & "The document is not reattached to Normal.dotm." _
            & vbCrLf & vbCrLf & "Only files created from a template with Detach Template Tip style can be removed.", _
            vbExclamation, "Not supported"
        Exit Sub

AttachTemplateFailed:
        MsgBox "Couldn't attach the normal template to this document.", vbCritical, "Error"
        Exit Sub

CleanupFailed:
        MsgBox "Could not clean up some of the tips notifying you to detach the template. You might have to clean them up yourself.", vbExclamation, "Cleanup failed"
        Exit Sub

    End If

End Sub