M2EE error - Detected unique constraint violation

Hi guys,    I am having this issue when I try to run the application locally This caused me unable to run the application.     May I know how can I resolve this issue?   Thank you so much
1 answers

Hi Renee,


did you recently change the settings (Project → Settings → runtime)  where the uniqueness is calculated?


Or did you recently upgrade the project to mx9? 


In the past Mendix gave you the option to choose where the uniqueness was being set, runtime or in the database. From (I believe) Mendix 9, this is always in database. Mendix developed the MigrationToolkit  to help you remove the duplicate values and enable the “database”  variant of the uniqueness validation.


Have a look at: 



You can contact Mx support for the toolkit.