Hi....I need a Validation rule that says once a certain custom Check Box field has been ticked, the Opportunity is no longer editable. Check Box will only be accessible by System Admin.  Reason is we will be driving certain other process from a finalised Opportunity and can't have any of the details changed once it is being used in the other processes....thanks

Hi....I need a Validation rule that says once a certain custom Check Box field has been ticked, the Opportunity is no longer editable. Check Box will only be accessible by System Admin.  Reason is we will be driving certain other process from a finalised Opportunity and can't have any of the details changed once it is being used in the other processes....thanks