Wont let me disconnect

Im using a Pc running windows 10, i use a WD My passport ultra external drive, but when ever i go to disconnect it from the pc i keep getting a message informing me that another program is using the drive and to not disconnect the drive from the pc, but i’m not aware of any programmes using the drive, so can anyone help with this matter please?

Hello,

When this happens you can turn the computer off and disconnect the drive while the computer is off.

Hamlet thanks for you reply, yea i know that but its a pain and sometimes time consuming.