User Exit

hi,

In transaction IA01 (Create equipment task list), I have to check for a maintenance package for each of the operation in the task list. If maintenance package is not assigned to the operation, then i need to display an error message. After this, I need to clear the error message and assign the maintenance package to the operation required. Can I do this enhancement in the User Exit CPRE0001? Please confirm.

thanks

barnita.