Diagnosis
If a referenced criteria field for the subscription generator ismissing (e.g. due to transport of a publication modification/deletioninto the system), the subscription generator can no longer be used andthe created subscriptions will be deleted.
The system usually sets the subscription generator automatically tostatus 'To Be Deleted', so that during the next subscription agent runthe subscriptions and assignments to sites are deleted. As soon as thesystem is consistent again, the subscription generator will deleteitself.
This automatism did not work in the current case: The referencedcriteria field cannot be found, but the subscription generator does nothave the status 'To Be Deleted'.

Procedure
Set the subscription generator to status 'To Be Deleted'.