Read once, copy to two disks

In the Export → Copy workflow, you can select a second destination disk. In suitable conditions, Merceq reads the source once and writes to the main destination and backup disk; it writes and reads back the copies on both disks separately to verify them. With some current file/disk conditions, this task may run sequentially.

If there’s a problem with the backup disk, completed copies on the main disk are kept; the report also shows what’s missing from the backup. If the main destination fails, the task stops too. A separate ASC MHL record is kept for each disk.

This option isn’t on the Copy to disk first screen; it’s in the Copy method while exporting. Links created on the same disk aren’t an independent second copy, so they don’t count as a backup.

How to select it: Chapter 8. Export your selections — Write to a second disk too.