form personalization + making the Header & Lines readonly based on condition on order organizer form

Hi All,

Can any one please tell me how to suppress the error message FRM - 41050: You cannot update this record.

i am getting that message through form personalization. In my case i should not make the block property to "True" . I am writing this trigger when-new-record-instance

Requirement1 : based on some conditions (Order Type & status) am making the Header & Lines of Order Readonly .

Requirement2 : based on some conditions (Order Type & status) am making the Header & Lines of Order Editable .

Thanks in Advance ..