It could be a great pain for those who love Apple, for a large number of videos in the iTunes library is in M4V format. Those M4V files are protected by DRM, which means that those files we bought from iTunes or shared from our friends cannot be freely edited, played and shared with some other friends (or put to our portable devices). Therefore, what we need to do first to enjoy the M4V files is to remove DRM from M4V. With a decent DRM Converter, this article tells us how to make it step by step.
Please first of all, download DRM Converter. After downloading, install and launch the program.
Click "+" to add a M4V file or files to the program:

The output profile shows M4V by default. Therefore, there’s no need to reset it. What we can do next is to click
to make some other necessary settings like this:

Next, click OK to end with the setting.
After all the above process is done, click
to start M4V DRM Removal. At the same time, iTunes will run and the file will be played automatically. You are not supposed to close the window of the playing video. After a little while, the procedure will finish.
Now, click Find Target to find the protection-removed M4V file.
Knowledge about DRM
Digital rights management (DRM) is a term for access control technologies that can be used by hardware manufacturers, publishers, copyright holders and individuals to limit the use of digital content and devices. The term is used to describe any technology that inhibits uses of digital content not desired or intended by the content provider. The term does not generally refer to other forms of copy protection which can be circumvented without modifying the file or device, such as serial numbers or keyfiles. It can also refer to restrictions associated with specific instances of digital works or devices.
With professional DRM Converter, you will never again be bothered by the protection of M4V files so that you can play those files in whatever way you'd prefer.
Sounds Good?