Is there a way to get the last NDF file READ/Access date / time? I have found a mysterious NDF file in my DB. Can't tell if it contains valid data or if the file is dead.

I'd like to remove it but I cannot tell if the file is in use by SQL Server. Windows Last Modified Date is 2 years ago, but for SQL files that is not reliable because SQL uses it's own drivers to access its files.

How can I tell what the last access time (either to read or to write) is for particular NDF file in a db?

Thanks!
Another option is to use sysinternals process utilities especially :

make sure you use the filter button to filter out unwanted things :-)

Process Explorer
Find out what files, registry keys and other objects processes have open, which DLLs they have loaded, and more. This uniquely powerful utility will even show you who owns each process.

or 

Process Monitor
Monitor file system, Registry, process, thread and DLL activity in real-time.