All picked parts must be unpicked before you can perform 'Undo release' on a production work order (PWO).

If the 'Undo' button in work order operation (WOO) is grey, this is because it is not available when there is an active work log running.

 By pressing 'Pause', the Work Log element will get an ENDTIME and 'Undo' in work order operations (WOO) will be available.  

The buttons 'Start' and 'Continue' are grey too as long as there is a work log active and running. 

The user will have to 'Pause' the production , then choose 'Undo' to get the WOO back to status '3'. 

If there is several steps on the operation or more than one operation that is started the user will have to perform this on those too. 

When all work order operations (WOO's) have status 3, the user can select "Undo release" in the PWO main application and from here cancel the production work order (PWO) or modify the structure and start over again.