How to Remove the device in safety

[DAMALIS]

When I connect a HDD into a external USB I can not safely remove by clicking the "left" on the icon in question. I have a windows message saying that I can not do. But if I click "right", I open a window and I stop my DD px.
Then I realize that in the device manager I have a yellow question mark on the "mass storage device".
If I uninstall it it is reinstalled correctly to restart windows but the problem come back if I stop vx again my device.
I did not have that concern before.
How can I solve this problem of course start a full restoration of the PC.

[jasonR]

Without removing your external hard drive, go into Device Manager and tell us if there's something that appears with the famous yellow triangle.

[DAMALIS]

I opened all the sections and NO does triangle or yellow question mark when you start windows.
I repeat the operation with external HDD it does not always.
I get the message: can not stop the device "generic volume"
I have to click "right", the I a message telling me that I remove the device, but I have a "yellow exclamation on the device mass.
In checking the properties I get the message below:

"Windows can not use this hardware device because it was prepared for a controlled ejection, but was not removed from the computer. (Code 47)".

when I reboot the PC the yellow has disappeared.