Completely remove additional data file from SQL Server 2012 DB Hope someone can help me on this one.

I have created by mistake an additional data file in the incorrect file group, I need to either remove the file completely or move the file to the default file group. Looks like changing files from one file group to another is not possible?

The data file is empty so I tried removing the file using alter DB remove file, when I run DBCC showfilestats, the file is gone, but when I check SYS.master_files, I can see still the entry of the file I want removed.
Is there a way to remove it completely, even deleting it physically from the server as I need to recover the space? 

Kind regards,
Jose.
Looks like changing files from one file group to another is not
  possible?


Correct, you would need to create a new file on the correct filegroup and recreate all your objects on the correct filegroup (if any existed) to move them, as you cannot move a file between filegroups.


  The data file is empty so I tried removing the file using alter DB
  remove file, when I run DBCC showfilestats, the file is gone, but when
  I check SYS.master_files, I can see still the entry of the file I want
  removed. Is there a way to remove it completely, even deleting it
  physically from the server as I need to recover the space?


I've seen this before in SQL Server 2012. If you query sys.master_files you will see the drop_lsn field has an LSN value in it for this file. This indicates the LSN at which this file was dropped. You need to perform a log backup to clear this value, then it will disappear from the DMVs.