Why can't I read encrypted DVDs after installing libdvdread4?

Question

I have already installed libdvdread4 and I still get the message:

Could not read DVD. This may be because the DVD is encrypted and a DVD decryption library is not installed.

Solution

libdvdread4 alone is not sufficient to play DVD movie discs. For your convenience, Ubuntu includes a nice metapackage to install most libraries and codecs to watch media: Ubuntu Restricted Extras .

This does not include libdvdcss2 from the Medibuntu repository yet. It's not included in Ubuntu for legal reasons as mentioned on the Ubuntu Wiki: RestrictedFormats/PlayingDVDs. See this answer on how to enable the Medibuntu repository and how to install this package.

In case you're still having problems playing DVDs and you have both libdvdread4 and libdvdcss2 installed, see this relevant question: Why does DVD playback still not work after installing libdvdcss2?, specifically this answer in it about setting the region code on your DVD player.

In case you're running an official derivative of Ubuntu, this might be relevant as well:

• What is the difference between Ubuntu, Kubuntu, Xubuntu and Lubuntu restricted extras/addons?