Entity Framework CTP4: where to put SetInitializer?

I am attempting to add Entity Framework, code first, to an MVC application that's been running with test data, using the CTP4 preview.

I am currently getting this error:

The model backing the 'SchedulerContext' context has changed since the database was created. Either manually delete/update the database, or call Database.SetInitializer with an IDatabaseInitializer instance. For example, the RecreateDatabaseIfModelChanges strategy will automatically delete and recreate the database, and optionally seed it with new data.

I do not want to generate a database at all, as I already have a database. So I tried adding the following to the SchedulerContext constructor:

Database.SetInitializer<SchedulerContext>(new CreateDatabaseOnlyIfNotExists<SchedulerContext>());

which had no effect at all -- I got the same error the next time it ran. The error seems to occur when it is executing a LINQ statement that accesses the database -- the first, I think.

Where should I put this statement, or is this statement the answer to this problem at all?