Ubuntu – CD/DVD drive not mounted when inserted with Disc of any kind

I just noticed that if a insert a CD or a DVD of any kind, the Drive will start spinning but it will not show the mounted disc. Earlier it used to ask me what to do with the media inserted. Now it doesn't even do that. I ran the following commands in terminal:

$ eject -n
eject: device is `/dev/sr0'

$ sudo mount -o ro,unhide,uid=1000 /dev/cdrom /mnt/cdrom
mount: mount point /mnt/cdrom does not exist

What can I do to get the functionality back on my drive? I am running Ubuntu 11.10.

Updates

• thanks Waltinator: I ran the 'dmesg' but don't know what I'm looking for. Im a newbie on this. The same thing with the 'ls -rlt /var/log' command. Should I create the directory for the mount? at this point really don't know what to do. – Cisco Sán 7 hours ago

• After I successfully inserted a CD, following are the first 3 lines of dmesg command:

  $ dmesg
  [ 4804.416018] wlan0: no IPv6 routers present  
  [ 8214.125450] ISdit ISO 9660 Extensions: Microsoft Joliet Level 3  
  [ 8214.136556] ISO 9660 Extensions: RRIP_1991A  
  

  Reply by Waltinator:

  The first line is a previous event, my wireless going online. The next 2 lines are a good result. The number in square brackets is "seconds since boot", the rest of the line is usually helpful. And no, you should NOT create the mount point. Let's try to get the automatic mounting to work. – waltinator

• These are my last 3 lines of dmesg:

  [ 18.130819] init: plymouth-stop pre-start process (1396) terminated with status 1  
  [ 28.780011] wlan0: no IPv6 routers present  
  [ 505.632119] CE: hpet increased min_delta_ns to 20113 nsec
  

  Reply by waltinator:

  It looks like your CD/DVD drive is not connected to the data bus, and not causing an interrupt when you insert a platter. Try dmesg | grep -A8 CD-ROM which should show you what the system thought was available when it came up. – waltinator

• This is my terminal output:

  $ dmesg | grep -A8 CD-ROM
  [0.774351] scsi 0:0:0:0: CD-ROM HL-DT-ST DVD+-RW GSA-T40N A100 PQ: 0 ANSI:  5
  [0.778117] sr0: scsi3-mmc drive: 24x/24x writer dvd-ram cd/rw xa/form2 cdda tray
  [0.778122] cdrom: Uniform CD-ROM driver Revision: 3.20
  [0.778282] sr 0:0:0:0: Attached scsi CD-ROM sr0
  [0.778340] sr 0:0:0:0: Attached scsi generic sg0 type 5
  [0.780416] Freeing unused kernel memory: 984k freed  
  [0.780732] Write protecting the kernel read-only data: 10240k  
  [0.780986] Freeing unused kernel memory: 20k freed  
  [0.786331] Freeing unused kernel memory: 1400k freed  
  [0.804912] udevd[90]: starting version 173   
  [0.874178] r8169 Gigabit Ethernet driver 2.3LK-NAPI loaded  
  [0.874208] r8169 0000:02:00.0: PCI INT A -> GSI 16 (level, low) -> IRQ 16
  

  Reply by waltinator:

  OK, your system sees the drive. Can you open and close the tray with eject and eject -t? Run udevadm monitor while you insert a CD (type ^C when done) and see if you get "change" and "add" messages. – waltinator

• eject works perfectly; eject -t does nothing.

  $ udevadm monitor
  KERNEL[13771.009267] change /devices/pci0000:00/0000:00:1f.1/host0/target0:0:0/0:0:0:0/block/sr0 (block)
  UDEV [13773.878887] change /devices/pci0000:00/0000:00:1f.1/host0/target0:0:0/0:0:0  /block/sr0 (block)
  

• Terminal output of sudo hwinfo --cdrom:

  $ sudo hwinfo --cdrom
  hal.1: read hal dataprocess 2753: arguments to dbus_move_error() were incorrect,   assertion "(dest) == NULL || !dbus_error_is_set ((dest))" failed in file ../../dbus/dbus-errors.c line 280.  
  This is normally a bug in some application using the D-Bus library.  
  libhal.c 3483 : Error unsubscribing to signals, error=The name org.freedesktop.Hal was not provided by any .service files  
  22: SCSI 00.0: 10602 CD-ROM (DVD)                               
    [Created at block.247]  
    Unique ID: KD9E.JgkxTS4hgl2  
    Parent ID: 3p2J.gdUMCD83e+E  
    SysFS ID: /class/block/sr0  
    SysFS BusID: 0:0:0:0  
    SysFS Device Link: /devices/pci0000:00/0000:00:1f.1/host0/target0:0:0/0:0:0:0  
    Hardware Class: cdrom  
    Model: "HL-DT-ST DVD+-RW GSA-T40N"  
    Vendor: "HL-DT-ST"  
    Device: "DVD+-RW GSA-T40N"  
    Revision: "A100"  
    Driver: "ata_piix", "sr"  
    Driver Modules: "ata_piix"  
    Device File: /dev/sr0 (/dev/sg0)  
    Device Files: /dev/sr0, /dev/scd0, /dev/disk/by-id/ata-HL-DT-ST_DVD+_-RW_GSA-T40N_K048BJ74257, /dev/disk/by-path/pci-0000:00:1f.1-scsi-0:0:0:0, /dev/cdrom, /dev/cdrw, /dev/dvd, /dev/dvdrw  
    Device Number: block 11:0 (char 21:0)  
    Features: DVD  
    Config Status: cfg=new, avail=yes, need=no, active=unknown  
    Attached to: #17 (IDE interface)  
    Drive Speed: 31  
    Volume ID: "Movie"  
    Publisher: "INTERVIDEO"  
    Creation date: "20050424162207000"