You can use the PV resize tool in the Extended Tools Menu if this was a H/W RAID setup (if this was setup with the Areca 1160) for your additional drives.
In such cases units appear as a MD0 that have been previously staged as a software RAID on them and not necessarily created with our software sometimes we have seen this happen. Outside of this, it would be necessary for us to view the logs and sent to support@open-e.com . Thank you for joining the forum!