“When I tried to play a Blu-ray disc, I get an error message that says ‘This Blu-ray Disc needs a library for AACS decoding’ on the VLC media player. What’s wrong with this? Why can’t I directly play back the Blu-ray discs with VLC media player?”

As one of the most popular media player software tools, VLC media player has quite a few functions for people to fully enjoy movie experience. You could use VLC media player to do a lot of things, such as editing videos, converting videos, downloading online live streams, etc. Some people have been reporting the error message of “This Blu-ray disc needs a library for AACS decoding” while playing Blu-ray discs. What’s wrong with this? How can you solve “This Blu-ray disc needs a library for AACS decoding” for VLC media player? Check the below content to learn the solutions.

Causes of this error in VLC

You may firstly want to learn the possible causes of “This Blu-ray disc needs a library for AACS decoding” error in VLC media player. We have investigated this particular by looking at some methods that other users in a similar situation have successfully solved this error. Based on our investigation, there are a couple of common scenarios that will trigger this particular error message:

Blu ray disc needs a library for AACS decoding

The below are the common causes of “This Blu-ray disc needs a library for AACS decoding” error in VLC media player. You might try to check these below:

  • Blu-ray disc is protected by AACS and BD+ technologies
  • Nowadays, most commercial Blu-ray discs are protected by AACS and BD+ technologies, which protect the Blu-ray discs from being copied or played back without authorization. Because of this, the standard library is not enough to playback these disks. In this scenario, the solution is to install the libaacs library.

  • The KeyDB.cfg file is missing
  • Another common reason why Blue-ray playback fails with this particular error is the KeyDB.cfg file is missing from your computer. This file is needed by the libaacs library.

    If you’re struggling to resolve this particular error message, check the below content to learn the detailed solutions.

    Method 1: Add libraries files to AACS in VLC player

    Then, how to solve the “This Blu-ray disc needs a library for AACS decoding” error on VLC media player? The first solution is to add library files for removing the AACS and BD+ protections. You need to download a file from a third-party site. While your browser may show it as unsafe. We have scanned the files and found them to be safe to use.

    Blu ray disc needs a library for AACS decoding

    You could follow the below guide to learn how to download and install library files to AACS for VLC media player:

    1. Visit this VLC Blu-ray library page.
    2. Type in the URL in the address bar and hit enter.
    3. You may see a warning showing the site does not have an SSL certificate.
    4. Click on the continue link if you want to proceed.
    5. Under Keys Database, click on the get the file link.
    6. It will download the KeyDB.cfg file.
    7. Next, under the AACS Dynamic Library section, click that file hyperlink associated with your VLC Media Player version.
    8. Once downloaded, copy the KEYDB.cfg file.
    9. Press Windows Key + R to open Run.
    10. Type %Appdata% and click OK.

    Blu ray disc needs a library for AACS decoding

    11. In the Roaming folder, click the New folder icon on top.
    12. Name the folder as aacs.
    13. Open the newly created aacs folder and paste the KEYDB.cfg file copied in step 5.
    14. Now, open the download folder and copy the libaacs.dll file to your clipboard.
    15. Open File Explorer and navigate to the following location: C:\Program Files\VideoLAN\VLC or C:\Program Files(x86)\VideoLAN\VLC

    Blu ray disc needs a library for AACS decoding

    16. Paste the copied libaacs.dll file inside the VLC folder.
    17. Once done, launch VLC Media Player and try playing the Blu-ray disc that was triggering the Blu-ray disc that needs a library for AACS decoding error previously.
    After copying the required library files to the correct folder, the VLC Media Player should have solved the error of “This Blu-ray disc needs a library for AACS decoding” and play the Blu-ray disc smoothly.

    Method 2: Use Leawo Blu-ray Ripper to remove AACS upon Blu-ray disc

    Another solution to fix “This Blu-ray disc needs a library for AACS decoding” error is actually to remove the AACS and other disc protections upon Blu-ray discs, and convert protected Blu-ray discs to digital videos for unlimited playback. There are quite a few Blu-ray disc converter tools, but quite few Blu-ray converters could remove the AACS and other disc protections upon Blu-ray discs. Leawo Blu-ray Ripper could.

    With advanced disc decryption technologies, Leawo Blu-ray Ripper could help you remove the AACS, BD+ and the latest MKB protection upon Blu-ray discs, and then convert Blu-ray discs to digital video files. It could decrypt, rip and convert Blu-ray to MP4, BDMV to MKV, Blu-ray to AVI, Blu-ray to WMV, etc., and extract audio off Blu-ray movies to save in MP3, AAC, FLAC, etc. You could use Leawo Blu-ray Ripper to remove AACS protection upon Blu-ray discs and convert protected Blu-ray discs to digital videos to avoid “This Blu-ray disc needs a library for AACS decoding” error.

    The below guide would show you how to remove the AACS and other protections upon Blu-ray discs with Leawo Blu-ray Ripper. At first, download and install this Blu-ray to video converter on your computer. (Mac users should download the Leawo Blu-ray Ripper for Mac) Meanwhile, insert source Blu-ray discs into the Blu-ray drive for converting.

    • Leawo UHD Ripper
    • Leawo UHD Ripper

      ☉ Decrypt and rip 4K Blu-ray discs, folders and ISO image files
      ☉ Convert 4K Blu-ray to MP4, MKV, AVI, MOV, FLV, and other 180+ 4K/1080P/720P/regular files
      ☉ Convert 4K Blu-ray movies in Full Movie, Main Movie or Custom Mode
      ☉ Edit 4K Blu-ray movies like trimming, cropping, adding watermark, applying 3D effect, etc.

    Note: Leawo UHD Ripper is a module built in Leawo Prof. Media.

    Step 1: Enter Blu-ray Ripper module

    Launch Leawo Prof. Media and then click “Convert” button on the sub-menu or “Blu-ray Ripper” button in the middle to enter the “Blu-ray Ripper” module.

    Step 2: Add source Blu-ray disc

    Under the “Convert” module, click on “Add UHD/Blu-ray/DVD” to add source Blu-ray disc by choosing “Add from CD-ROM” option on the drop-down panel.


      1. Leawo Blu-ray Ripper offers 3 options to load source Blu-ray movie: Full Movie, Main Movie and Custom Mode. Full Movie allows you to import all titles, and Main Movie only imports the longest title by default but allows you to switch, while under Custom Mode you could freely choose any title(s) for loading. Choose the one according to your needs and load source Blu-ray movies.

      2. You could play back loaded Blu-ray movie files, select subtitles and audio tracks, edit loaded Blu-ray movie titles, etc.

    Step 3: Set output format

    Hit the button next to the “Add Photo” button and then click “Change” option on the drop-down panel to enter the “Profile” window. Choose output format from either “Format” or “Device” group according to your device. VLC media player accepts most video file formats. For higher quality, choose MKV Video from “Format > Common Video” or select one from the “Lossless Video” group as output format.


    You could adjust video and audio parameters of output files to make sure the output files meet your media or player exactly, including video bit rate, aspect ratio, resolution, audio codec, sample rate, audio bit rate, audio channel, etc. To do these, just click the “Edit” option on the drop-down panel next to the “Add Photo” button.

    Step 4: Set directory and start converting Blu-ray disc

    On the main interface, click the “Convert” in green on the sub-menu and then set output directory in the “Save to” box to save output video file. After that, hit the “Convert” button at the bottom to start converting Blu-ray disc for VLC media player.

    It should be noted that the Blu-ray disc protection removal happens in the background, requiring no human interfere. But you need to make sure your computer Internet is well connected. Wait for the conversion to complete then. When the conversion completes, the Blu-ray disc protection would be successfully removed and you will get digital video files from source Blu-ray disc for smooth playback.

    Method 3: Try another media player that doesn't require an AACS installation

    The final recommended solution for fixing the “Blu-ray disc needs a library for AACS decoding” is to make use of VLC media player alternatives. There are quite a lot of alternatives to VLC media player that could do far more than VLC can do for you. Leawo Free Blu-ray Player is one of the few VLC media player alternatives that could help you play back all Blu-ray discs, regardless of Blu-ray disc protections like AACS and BD+.

    Leawo Blu-ray Player could play back Blu-ray movies in disc, BDMV folder and ISO image files, no matter your Blu-ray movie files are AACS, BD+ or the latest MKB protected. Also, the region-free feature makes it able to play back Blu-ray movie files regardless of your Blu-ray movie region restrictions. It’s totally free. What’s more, it could play back DVD, up to 4K video, ISO file, and audio files for totally free at high quality.


    There are quite a few solutions to help you solve the error of “This Blu-ray disc needs a library for AACS decoding”. You could try any of the above-mentioned solutions. Among these 3 solutions, without doubt, trying Leawo Blu-ray Player should be the easiest and most practical one, using Leawo Blu-ray Ripper helps you easily play Blu-ray disc on various media players and devices smoothly, while adding AACS library for VLC media player seems to be a little bit complicated.