This Blu-ray needs a library for aacs decoding“This Blu-ray disc needs a library for aacs decoding, and your system does not have it.” You read this because you got a Blu-ray error when trying to play a Blu-ray disc with VLC Player on your computer. VLC is a good player software for Blu-ray content on Windows, macOS and even Linus, but it still can’t play Blu-ra disc that protected by aacs or BD+ nonetheless. Therefore, if you want to enable VLC to play those commercial Blu-ray discs, you must find the valid library for aacs decoding and put it into the right place, so that VLC can invoke it for decrypting Blu-ray content.

More Errors that you May Got when Playing Blu-ray with VLC

A library for aacs decoding

What is AACS? AACS is short for Advanced Access Content System which is a standard for DVD and Blu-ray content distribution and digital rights management. Accordingly, with the protection of AACS, all unauthorized access to the DVD and Blu-ray content will be banned. And that is the reason why you cannot play the Blu-ray disc on VLC. Luckily, many AACS decryption keys have been extracted and published on the internet, enabling decoding the AACS protected DVD or Blu-ray Media with third-party software such as VLC. So those extracted decryption keys are the library for aacs decoding that you need when playing Blu-ray disc with VLC.

Where to download AACS decoding library and how to install it to VLC

To fix “this Blu-ray disc needs a library for aacs decoding…” error, there are two files that you need to implement to your VLC.

  1. KEYDB.cfg file – this file is used by aacs decoding file.
  2. libaacs.dll – this is the aacs decoding file

Step 1 Go to, you will receive the privacy error telling you that Your connection is not private. Click on the Advanced button to enlarge the error explanation tab and click Proceed to (unsafe).


Step 2 Download keys database file and AACS dynamic library file onto your computer. You should download the right version of AACS dynamic library according to your system. Since I am in Windows 10 60bit, so I will download the VLC 64 bit on Windows version.

Step 3 Install the downloaded files.

For Windows:

  1. Put KEYDB.cfg in C:\Users\[Your User Name]\AppData\Roaming\aacs. You can press Win + R to launch the Run application, and enter %appdata% into the Open text filed. Then click OK to open the directory of C:\Users\[Your User Name]\AppData\Roaming, then Create a folder name “aacs” and copy the cfg into the folder.
  2. Put libaacs.dll in your VLC installation directory.

For Mac:

  1. Put KEYDB.cfg in ~/Library/Preferences/aacs/ (create it if it does not exist).
  2. Put libaccs.dylib in /usr/local/lib/ directory (create it, if it does not exist).

Note: since has been out of update for years, so please follow our instruction to install those files.

Step 4 Restart VLC and open the Blu-ray disc once again.

Now you probably have fixed the “This Blu-ray Disc needs a library for AACS decoding, and your system does not have it” error. Make sure that you have followed the fix guide carefully. If it doesn’t work. Please repeat the steps once again.

If you still cannot play your Blu-ray movie with VLC. I will recommend you to use a third-party Blu-ray Player software to open the Blu-ray disc.

Best VLC alternative to play Blu-ray disc on Windows and macOS

If you don’t want to see the Blu-ray errors when playing Blu-ray contents with VLC or you just can’t fix the “This Blu-ray Disc needs a library for AACS decoding, and your system does not have it” error. Then a third-party Blu-ray Player software is your best choice.

  • Embedded with all necessary decoding library for playing all DVD and Blu-ray disc, you don’t have to handle with the aacs decoding library missing problems.
  • Play AACS and BD+ protected Blu-ray 1080p/720p HD videos.
  • Play DVD disc, folder, and ISO file on computer.

How to Play AACS Protected Blu-ray Disc with Blu-ray Player instead of VLC

Step 1 Install the Blu-ray Player software mentioned above on your Windows or Mac.

Step 2 Launch the Player and click Open Disc on the middle menu of the interface.

Then you are free to enjoy your Blu-ray movie on your PC now.

Besides turn to a third-party player, you have another feasible solution which is to rip the Blu-ray disc to a digital video file then play the video with any ordinary player on your computer. To rip a Blu-ray disc, you need to appeal to Blu-ray Ripper.