Try using upright single and double quotes.
Public Sub DisplayUnexpectedError(ErrorNumber As String, ErrorDescription As String)
' Note: since this is a universal error handling procedure, it does not have error handling
MsgBox "An error has occurred in this application. " _
& "Please contact your technical support and " _
& "tell them this information:" _
& vbCrLf & vbCrLf & "Error Number " & ErrorNumber & ", " _
& ErrorDescription, vbCritical, "My Application"