Moving your TempDB locations should be performed outside production.
Check Current Temp DB Locations:
SELECT name, physical_name AS CurrentLocation
FROM sys.master_files
WHERE database_id = DB_ID(N’tempdb’);
GO
Move the Temp2 or any additional Temp databases:
USE master;
GO
ALTER DATABASE tempdb
MODIFY FILE (NAME = temp2, FILENAME = ‘T:\MSSQL\DATA\tempdb_mssql_2.ndf’);
GO
Check Current Temp DB Locations again:
SELECT name, physical_name AS CurrentLocation
FROM sys.master_files
WHERE database_id = DB_ID(N’tempdb’);
GO
Note: you will need to restart the MSSQLSERVICE for your instance for the changes to take effect.