In the event of a failure, further transfers should be postponed until the cause is determined.
A canned query is provided for detection within the destination server of systems that have failed the transfer. This query can be monitored whilst transferring batches of systems, in order to quickly detect failures.
Any failures will also generate an audit event that will be reported to the destination server and also logged to the Drive Encryption log file on the system.
Recommended investigation
Check the Trellix ePO - On-prem product client events audit for the system and their details
Check the Drive Encryption log (DriveEncryption.log)
Check the Trellix ePO - On-prem orion log
Check the agent handler logs
Once the issue has been resolved, the Drive Encryption service on the system should be restarted in order to kick off the process again; this can also be accomplished by restarting the system.