Room not found in design database


I'm currently working on a model and have deleted a room, however, the following message has came up... "room not found in database. To prevent possible database corruption design database will now shut down" and the project is now inaccessible. This is causing a major problem as I have taken the model quite far and now I cant access it. Can this problem be resolved without having to start again?

Kind regards, 

Claire Mackenzie