Most likely there is some fault with it. Is it listed in red in Surveyor or with a red exclamation in CMP? If so, either the loco or one of its dependencies, such as abogey, is faulty (in CMP, you'd see a red puzzle piece if it was a dependency and not the loco itself.) You'll need to fix it. Unfortunately, a lot of that older content was made to more-loose standards than modern content, and since it's not hosted on the DLS, it's up to you to fix it yourself. There's a thread in the TS2010 forum on a list of errors and how to fix them.