Viewing directory of a mapped drive

I'm using the following query to view files/folders in a given directory. It works locally, but when trying to view a mapped drive I get... "The system cannot find the path specified." I have the permissions for the whole mapped drive set to the service account associated with SQL, but it is still not working. declare @files table (ID int IDENTITY, FileName varchar(100)) insert into @files execute xp_cmdshell 'dir Z:\ /b' select * from @files End goal is to create a stored procedure that will transact specific file names into a table.