unable to add an ubutu dvd

[Battant]

Hello,

1. If I insert my ubuntu 14.04.3 dvd, there is no dialogue box shown to suggest me to add this cd rom to the synaptic.

2. In synaptic if I choose to add a cd rome in edit menu a dialog box asks me to insert the dvd in my dvd rom. but after this action
I get this exception:

E: Failed to mount the cdrom.

Expected result :

When I insert my ubuntu 14.04.3 dvd, a message box should ask me if I want to open synaptic to add this dvd like on an other distribution

Is it a bug and if yes could you please fix it ?

Best regards

Battant