External Hard drive refuses to be safely remove even nothing uses it

[SakataUmi]

My external hard drive refuses to safely remove. Keep on saying it is in use. I already check on resource monitor and no program are using it.

 

[dfk]

Sometimes this does happen, you can either try closing apps or log off user/reboot. Can also try going to Disk Management > right click the external disk and below and select 'Offline'.

Or you can try Mountvol: "Removes the volume mount point from the specified directory, dismounts the basic volume, and takes the basic volume offline, making it unmountable. If other processes are using the volume, mountvol closes any open handles before dismounting the volume. "
http://superuser.com/questions/295913/how-to-mount-and-unmount-hard-drives-under-windows-the-unix-way