File ID of database ID cannot be shrunk as it is either being shrunk by another process or is empty
Microsoft KB suggest that the error may be resolved by restarting the SQL Server service or take database offline and then put the database online again. Here is the KB link.
In some cases, rebooting the server is not an option, and should be always the last option, you can trick it (reinitialize) by increasing the data file size (e.g. 1 MB).
USE tempdb; SELECT name, size * 8 / 1024 FROM sys.database_files;
Find out the size of the database and add 1 MB.
ALTER DATABASE tempdb MODIFY FILE (NAME = 'tempdev', SIZE = <current database size + 1 MB>);
After execute the command, DBCC SHRINKFILE should works again without any error message.
And always consider twice if you really need to shrink a database file. Cause it may cause a lot of problem like fragmentation.