Patching Windows Media Player

I’m writing this post on the request of @rudr4_sarkar. This is a very simple patch in which you can open multiple instances of wmplayer. It basically uses the ‘CreateMutexW’ API to create a mutex object with the string “Local\Microsoft_WMP_70_CheckForOtherInstanceMutex”.


The pseudo code would be something like this

HANDLE hMutex = CreateMutex(NULL, FALSE, L"Local\Microsoft_WMP_70_CheckForOtherInstanceMutex");
if (GetLastError() == ERROR_ALREADY_EXISTS) {


You just need to patch the ‘JNZ’ to a ‘JMP’ instruction, that will always jump to the good boy ๐Ÿ™‚


You can also do this on runtime by killing the Mutant handle using Process Explorer.


Here’s a small patch which I wrote for fun in C++ fully using the win32 API. I have included 2 versions. The first version works with both Windows 7 and 8, while the the other works with Windows 10.



After patching you should be able to open as many as windows you like and enjoy music and other tasks ๐Ÿ™‚

This is strictly written for educational purposes. The author doesn’t take any responsibility for your actions.


5 thoughts on “Patching Windows Media Player

Leave a Reply

Fill in your details below or click an icon to log in: Logo

You are commenting using your account. Log Out /  Change )

Google photo

You are commenting using your Google account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s

This site uses Akismet to reduce spam. Learn how your comment data is processed.