Odoo POS - Open a session

I'm new on odoo, when I open a session, loading stops in this part as picture shows, on console i got this warining:

2016-04-04 08:35:39,960 7157 WARNING test2 openerp.models: area.area.read() with unknown field 'users_ids'

2016-04-04 08:35:39,960 7157 WARNING test2 openerp.models: area.area.read() with unknown field 'capacities'

2016-04-04 08:35:39,960 7157 WARNING test2 openerp.models: area.area.read() with unknown field 'available_capacities'

2016-04-04 08:35:39,960 7157 WARNING test2 openerp.models: area.area.read() with unknown field 'area_id'

can someone help me please, thank you :)