That would be because the program Minecraft is JAVA based program.
What you're pinning to the taskbar (the minecraft executable from the installation folder)
that's actually used by the game
in order to run, what is run is usually the java executable
that is handling the program, usually javaw.exe/java.exe/javaws.exe
This java executable
is application independant
, which means that for every
program that you launch that requires Java, a new instance
will be launched and added to your Task Manager
. For example:-
I use a Java based program called PS3 Media Server
to stream video content to my PS3.
The program's executable is called PMS.exe
When I open PMS.exe
what is actually launched is an instance of javaw.exe
in my task manager
And so, since Windows
refers to this javaw.exe
in your task manager as a new and unrelated program,
it adds it to your taskbar.
Notice the two
green arrow program icons on my taskbar picture, the first one is the PMS.exe that I pinned to the taskbar, and the 2nd one is the javaw.exe process
that is handling the program.
So in conclusion, what you've mentioned in your opening post is normal by design.