Veritas defines WORM and NON-WORM as follows:

• WORM: Enterprise Vault will set the retention period defined in an Enterprise Vault Retention Category to the objects written to an ECS Streamer Partition.
• NON-WORM: Enterprise Vault will not set the retention period defined in an Enterprise Vault Retention Category to the objects written to an ECS Streamer Partition.

With a NON-WORM partition:

• Even if a Vault Store is using a Retention Category that has a retention period, users using the Enterprise Vault Search Browser can select documents for deletion. Because there is no retention on the objects on the ECS, the ECS allows the deletion to succeed. For example, administrators use this method to set documents to be Retained Forever in Enterprise Vault so that the Enterprise Vault Expiration Task will not be run on the Partition but will still allow users to delete individual documents.
• Enterprise Vault Administrators can change the retention period of a Retention Category and can shorten it. Subsequent runs of the Enterprise Vault Expiration Task will act on the newly shortened retention period and will attempt to delete the content. The attempt will succeed because there is no retention on the object on the ECS.

ECS 3.x is supported as a WORM or NON-WORM enabled Enterprise Vault archive device for EV12 and EV14. When any Veritas Vault Store Partition is created and uses the ECS Streamer driver, select the box shown in Figure 6 to enable WORM storage, or clear the box to use NON-WORM.

Figure 6.        WORM or NON-WORM setting

This setting cannot be changed once the partition has been created.