Ubuntu backup failed

I have been trying to backup for my first time on Ubuntu 16.04 with Duplicati - 2.0.4.23_beta_2019-07-14 and I keep getting this error “System.NullReferenceException: Object reference not set to an instance of an object”

I have tried deleting/repairing the db, I also changed “concurrency-block-hashers” to 1. I have tried excluding to try to narrow down the exception but that didn’t seem to work either, any ideas?

Here is the stack trace
System.AggregateException: One or more errors occurred. —> System.AggregateException: Object reference not set to an instance of an object —> System.NullReferenceException: Object reference not set to an instance of an object
at Duplicati.Library.Main.Volumes.BlockVolumeWriter.AddBlock (System.String hash, System.Byte data, Int32 offset, Int32 size, CompressionHint hint) <0x7f4b3fc8a8 + 0x00084> in :0
at Duplicati.Library.Main.Operation.Backup.SpillCollectorProcess+<>c__DisplayClass0_0+<b__0>d.MoveNext () <0x7f4b444458 + 0x00d1b> in :0

Welcome to the forum!

What back end are you using?

I’m using Apache2
Server version: Apache/2.4.41 (Ubuntu)
Server built: 2019-08-21T20:43:05

Is job’s Destination screen Storage Type WebDAV? I’m not familiar with everything Apache has.

What does live log show leading up to the failure? I’d suggest About --> Show log --> Live --> Retry

–log-file and –log-file-log-level=retry can be set for unattended capture, if you prefer to log that way.