This may sound like a clone of several recent posts, but it isn't. At least the posted solutions don't work for me. So:
I recently noticed that I could not watch commercial DVD videos anymore.
DVDs that worked beautifully a few of months ago simply aren't recognized by the system anymore. Not on two 32 bit setups, not on two 64 bit setups.
I have installed libdvdcss2, libdvdnav4. libdvdread3 and libdvdread4 (and their 64 bit equivalents). I have installed win32-codecs-all (and w32codecs and w64codecs where relevant). But video DVDs are simply not recognized by the system.
Not on a stable 32 bit KDE install, where the only things I've added to the defaults are LibreOffice and libdvdread3, not on my 32 bit test install with Archie's 4.9.2 testing version, not on either of my 64 bit setups.
Data disks are recognized when inserted into the same optical drive, commercial video disks just aren't.
I cannot access them with VLC, SMPlayer, Xine, Dvd95 or vobcopy. They are simply invisible. Yet, if I insert a data DVD into the drive, it's immediately recognized.
I know that to watch a film on a DVD you shouldn't have to mount it, but I've tried mounting the disks anyway. Except ... I can't. Not with a line in /etc/fstab, not without one. I can mount data DVDs in more ways than I care to list; I can't mount commercial DVDs with movies.
Booting older kernels doesn't help either.
And yet I could watch the same films a couple of months ago. What's changed?