Completing Previous Backup Hangs

I’m on 23.0.1 on Linux. One of my backups was interrupted and now ever time it is restarted it gets stuck in Uploading filelist from previous interrupted backup forever. Here is what the live log shows:

  • May 12, 2026 10:20 AM: Uploading filelist from previous interrupted backup

  • May 12, 2026 10:19 AM: Removing file listed as Temporary: duplicati-20260505T060002Z.dlist.zip.aes

  • May 12, 2026 10:19 AM: Keeping protected incomplete remote file listed as Temporary: duplicati-20260505T060001Z.dlist.zip.aes

  • May 12, 2026 10:19 AM: Backend event: QuotaInfo - Started: ()

  • May 12, 2026 10:19 AM: Backend event: List - Completed: (2.032 KiB)

  • May 12, 2026 10:19 AM: A Task’s exception(s) were not observed either by Waiting on the Task or accessing its Exception property. As a result, the unobserved exception was rethrown by the finalizer thread. (The CancellationTokenSource has been disposed.)

  • May 12, 2026 10:19 AM: Backend event: List - Started: ()

  • May 12, 2026 9:53 AM: Setting custom SQLite option ‘shared_cache=true’.

  • May 12, 2026 9:53 AM: Setting custom SQLite option ‘threads=8’.

  • May 12, 2026 9:53 AM: Setting custom SQLite option ‘mmap_size=67108864’.

  • May 12, 2026 9:53 AM: Setting custom SQLite option ‘cache_size=-65536’.

  • May 12, 2026 9:53 AM: Setting custom SQLite option ‘journal_mode=WAL’.

  • May 12, 2026 9:53 AM: Setting custom SQLite option ‘temp_store=MEMORY’.

  • May 12, 2026 9:53 AM: Setting custom SQLite option ‘synchronous=NORMAL’.

  • May 12, 2026 9:53 AM: The operation Backup has started

  • May 12, 2026 9:53 AM: The operation Backup has completed

  • May 12, 2026 9:53 AM: Setting custom SQLite option ‘shared_cache=true’.

Please read these, last updated 1 day ago, so should be nearby:

No Status or Details by Completing previous backup

“Completing previous backup” following update to latest (2.3.0.1)

The workaround is to set option disable-synthetic-filelist.
There are also several ways to check this is the problem present.
There is a fix being proven in a Canary release (channel for test).

The disable-synthetic-filelist got it through a successful backup. Should I leave this enabled?

Your choice. If you do, it should keep the performance issue away, but also stop synthetic filelist. Regardless, you can turn workaround off whenever bug is fixed, presumably whenever next Stable comes out.