You cannot delete versions that are used in planning units that are started or are assigned to axes on forms. You must remove references to versions from forms and assign another version to axes. At least one version must remain in the application.
To delete versions:
Select Administration, then Manage, then Dimensions.
Select Version.
Select the versions to delete.
Click Delete.
Click OK.
If planning units are started, you cannot delete versions associated with them.
Update and validate business rules and reports.