This is an old thread but this was the first hit on Google so I'm going to add my experience here. I was using SQL Server 2014 Enterprise while remote connected to the server.
I was attempting to restore a database from backup WITH REPLACE and RESTORE WITH NORECOVERY. Between the backup and my first transaction log I received the error indicated above. No databases on the server were able to be accessed; all received the same message. I was, however, able to access the other databases by connecting through a local instance of SSMS and it indicated that my intended target database was (Restoring...), as expected.
Turns out, all I had to do on the server instance of SSMS was restart SSMS. All was normal after that.