Please check server log generally its located at /var/log/openerp/openerp-server.log. There might be any python package missing.

What does your log-file tell you about the error? How do you run the server, using a deamon or manually on the commandline?

the server log: 

a lot of thanks for this help, odoo is the last software i need for migrate 100% from windows to linux :-)

Hi, edit the answer, in my computer, the instructions for install the last version of odoo don't work. Finally i can install odoo doing this (don't know if is the better way, i believe can help others).

Install postgresql with terminal

$ sudo apt-get install postgresql

Password for postgres user

$ sudo -u postgres psql postgres

postgres=# \password postgres  (write your password when terminal say)

(ctrl +D for exit)

Create a user as my linuxmint user:

$ sudo -u postgres createuser --superuser $USER ($USER automatically is your linux user)

$ sudo -u postgres psql (for change the new user password)

postgres=# \password USUARIO (change USUARIO/USER for your linux user and write your password)

CTRL + D for exit

Next, I download the .deb package from Odoo, change the permission of the file for all to write and read (don't know if necessary), then click and install. Next in terminal, write:

sudo su (for superuser access)

sudo service odoo start (must be OK, you can test with sudo service odoo status)

Go for your internet browser and write: localhost:8069, create the database following the instructions, and next, create one user for your Odoo company.

For me, it was OK and running well, please, if somebody can say if something is wrong it will can help others with same problem.