@bradeneuropeArthur
I have made that change to the line you suggested and still had no success.
I tried moving the contents of the SetupUserInterface sub into the m_sampleButton_OnExecute private sub and it now gets to the last message box.
Although the FileRev.Label is blank 
I checked vault and it should have a value of "A"
see code below:
Private Sub m_sampleButton_OnExecute(Context As Inventor.NameValueMap) Handles m_sampleButton.OnExecute
Dim strVaulrServerName1 As String = Connectivity.InventorAddin.EdmAddin.EdmSecurity.Instance.GetEdmLoginPreferences.Server
Dim strVaultName1 As String = Connectivity.InventorAddin.EdmAddin.EdmSecurity.Instance.GetEdmLoginPreferences.VaultName
Dim strVaultUserName1 As String = Connectivity.InventorAddin.EdmAddin.EdmSecurity.Instance.GetEdmLoginPreferences.UserName
Dim strVaultPassword1 As String = Connectivity.InventorAddin.EdmAddin.EdmSecurity.Instance.GetEdmLoginPreferences.Password
Dim results1 As VDF.Vault.Results.LogInResult
results1 = VDF.Vault.Library.ConnectionManager.LogIn(strVaulrServerName1, strVaultName1, strVaultUserName1, strVaultPassword1, VDF.Vault.Currency.Connections.AuthenticationFlags.Standard, Nothing)
Dim conn1 As VDF.Vault.Currency.Connections.Connection = Nothing
If results1.Success Then
conn1 = results1.Connection
MsgBox("Connected to Vault")
End If
moDocSvc = conn1.WebServiceManager.DocumentService
Dim Odoc As Document = g_inventorApplication.ActiveDocument
MsgBox(Odoc.FullFileName)
Dim VaultFile As String = Odoc.FullFileName.Replace("C:\_Vault-WIP", "$")
VaultFile = VaultFile.Replace("\", "/")
MsgBox(VaultFile)
Dim hh() As Autodesk.Connectivity.WebServices.File = moDocSvc.FindLatestFilesByPaths(New String() {VaultFile})
MsgBox(hh(0).Name)
MsgBox(" THE REVISION OF THE FILE = " & hh(0).FileRev.Label)
Exit Sub
End Sub