Products > PSOP > Documentation PSOP says my project changed during leveling. What does that mean? PSOP reads all the project and schedule information from the Primavera database. It writes the schedule it produces to this database. If any user (including you) has the project open while PSOP is running, they can modify the project. However, the project should never be modified (by you or any other user) while PSOP is running. If PSOP notices that the project has been modified, it exits to avoid the danger of corrupting the project in your database. For more information, click here and here. Back to FAQ