Please check you don't have any service that is running for third party defragmenting utility. If that's the case, stop the service.
Similarly with archiving/backup utilities that perform a background backup or indexing task.
That could be a reason because the HDD led is alway running.
Also I would check with Cristal Disk Info whether there are some S.M.A.R.T. issues.
Then if possible, quit your OS and restart the PC.