Customize validated proposal reference number

Hi,

Is anyone know how to change the reference number format of a validated proposal ?
Current format - PR2101-0004 (I need to change this for customize format)
Status -Validated (proposal is open)

Yes. Go to Setup–>Modules/Applications --> Commercial proposals module setup
First section you will find : Commercial proposal numbering models
Here you can change your ‘mask’.

Thank You. I changed it.