Windows 7 - Safety Remove a HDD (SATA)

In the icon tray, there is an icon for safety removing hardware and eject media. I'm using two HDDs. One where Windows 7 is installed and another where are some data are placed. By clicking on the icon, a context menu appears where my two HDDs are listed. If I click on the HDD where just my data are placed, I get an error message:

There aren't any applications opened which are currently in use or accessing the drive. Also after restarting my computer and try it again, the error message appears.

The reason why I want to eject the device is that working with the HHD, the performance decreased. There must be a performance issue with Windows and the device. Why this doesn't work and is there a possibility to plug out the HDD without manually removing the cable?

Hello skew

Have a look at these applications. They may shed some light on what is preventing your HDD from been removed
LockHunter is a free 64/32 bit tool to delete files blocked by any processes
UNLOCKER 1.9.1 BY CEDRICK 'NITCH' COLLOMB

Danny

Is this an internal HDD or an external? Internal HDDs don't need to be ejected, just power down the computer and disconnect the hdd.

As far as the message, when I run into it occasionally when attempting to eject an external USB drive, I ensure that no open applications are referencing the drive and make sure there's no current disk activity then pull the cable. I have never had a problem from doing this.

You can also access the device Properties in Device Manager and on the Policies tab you can set "Quick Removal" which disables write caching on the drive which makes the "Safely Eject..." dialog irrelevant.