Backup Failed - Could not find file "" - Help!

[Randy]

Hey everyone, I’m wondering if someone with more experience and intelligence can help me track down why I can’t get Duplicati to backup.

I consistently get the error "Error while running Backup - Could not find file “” ". For context, I am using portainer and setting up duplicati using the app template within portainer. I have tried to recreate the container multiple times using many different ways… app template, manual container configuration, and docker compose. I have mapped my drives correctly and verified that the container can see every directory. Everything has the proper permissions, and I can configure the backup and all “tests” for destination and source pass during backup configuration within the Duplicati UI. Every single time I get presented with the same error.

I greatly appreciate any help on this topic, as a good friend and I have searched endlessly for someone with a similar issue. Thank you in advance!

When I go to check the logs in duplicati, this is the larger error message I get:

Sep 8, 2023 11:48 AM: Failed while executing "Backup" with id: 1
System.IO.FileNotFoundException: Could not find file ""
  at System.IO.DriveInfo.GetDiskFreeSpace (System.String path, System.UInt64& availableFreeSpace, System.UInt64& totalSize, System.UInt64& totalFreeSpace) [0x00014] in <d636f104d58046fd9b195699bcb1a744>:0 
  at System.IO.DriveInfo.get_TotalSize () [0x00000] in <d636f104d58046fd9b195699bcb1a744>:0 
  at Duplicati.Library.Backend.File.get_Quota () [0x0000a] in <a11c194a0ed94b3ea73efea18edcd2ee>:0 
  at Duplicati.Library.Main.Operation.FilelistProcessor.RemoteListAnalysis (Duplicati.Library.Main.BackendManager backend, Duplicati.Library.Main.Options options, Duplicati.Library.Main.Database.LocalDatabase database, Duplicati.Library.Main.IBackendWriter log, System.Collections.Generic.IEnumerable`1[T] protectedFiles) [0x00291] in <9cab5b8f1b4f49ec980acae8e278968b>:0 
  at Duplicati.Library.Main.Operation.FilelistProcessor.VerifyRemoteList (Duplicati.Library.Main.BackendManager backend, Duplicati.Library.Main.Options options, Duplicati.Library.Main.Database.LocalDatabase database, Duplicati.Library.Main.IBackendWriter log, System.Collections.Generic.IEnumerable`1[T] protectedFiles) [0x00000] in <9cab5b8f1b4f49ec980acae8e278968b>:0 
  at Duplicati.Library.Main.Operation.BackupHandler.PreBackupVerify (Duplicati.Library.Main.BackendManager backend, System.String protectedfile) [0x0005f] in <9cab5b8f1b4f49ec980acae8e278968b>:0 
  at Duplicati.Library.Main.Operation.BackupHandler.RunAsync (System.String[] sources, Duplicati.Library.Utility.IFilter filter, System.Threading.CancellationToken token) [0x01048] in <9cab5b8f1b4f49ec980acae8e278968b>:0 
  at CoCoL.ChannelExtensions.WaitForTaskOrThrow (System.Threading.Tasks.Task task) [0x00050] in <9a758ff4db6c48d6b3d4d0e5c2adf6d1>:0 
  at Duplicati.Library.Main.Operation.BackupHandler.Run (System.String[] sources, Duplicati.Library.Utility.IFilter filter, System.Threading.CancellationToken token) [0x00009] in <9cab5b8f1b4f49ec980acae8e278968b>:0 
  at Duplicati.Library.Main.Controller+<>c__DisplayClass14_0.<Backup>b__0 (Duplicati.Library.Main.BackupResults result) [0x0004b] in <9cab5b8f1b4f49ec980acae8e278968b>:0 
  at Duplicati.Library.Main.Controller.RunAction[T] (T result, System.String[]& paths, Duplicati.Library.Utility.IFilter& filter, System.Action`1[T] method) [0x0026f] in <9cab5b8f1b4f49ec980acae8e278968b>:0 
  at Duplicati.Library.Main.Controller.Backup (System.String[] inputsources, Duplicati.Library.Utility.IFilter filter) [0x00074] in <9cab5b8f1b4f49ec980acae8e278968b>:0 
  at Duplicati.Server.Runner.Run (Duplicati.Server.Runner+IRunnerData data, System.Boolean fromQueue) [0x00349] in <30a34d71126b48248d040dda634ddad9>:0 ```

[gpatel-fr]

@Randy

For context, I am using portainer

Well, that’s the first time I see the word. Computer are long, life is short. Help will be limited from my part.

@Randy

I can configure the backup and all “tests” for destination and source pass during backup configuration

That don’t prove much about anything. For most backends - I think the only exception is Ftp backends - the ‘test’ during backup is very limited, it’s basically a verification that a list call don’t return an error. There is no attempt at writing a file. Just verified: it’s the same for the file backend.

FTR a simple search of this forum returns the following post:

Could not find file ""

Hi, I have Duplicati running on my Fedora Core server in a docker container. Duplicati is set up to backup 2 local folders to my QNAP NAS. I tried mounting the QNAP via nfs and via cifs. This setup used to work, but I reinstalled the OS on my server and now does not anymore. The backup job starts and after a few seconds throws the error “Could not find file “””. When starting the backup job via Commandline I receive the following stack trace Backup started at 9/11/2022 8:35:55 PM Checking remo…

It’s the very same error message so there is hope of finding a solution by fiddling with the container configuration.

[ts678]

There are also manually run tests available such as Duplicati.CommandLine.BackendTester.exe:

Before you start using a particular backend to use as a backup target, you can use the Backend Tester to get an indication of the integrity of that backend.

This one’s automatic, with some options. Give it a target URL, e.g. from Export As Command-line.

Using Duplicati from the Command Line
Using the Command line tools from within the Graphical User Interface

Duplicati.CommandLine.BackendTool.exe is a manual tool you could try if you don’t like automatic.

I don’t use Portainer or Docker (whose Docker image is this anyway?), so can’t solve configuration.

@Randy

I have mapped my drives correctly

Different vendors’ images do the mapping differently, so I don’t know what this means for your case.
For testing purposes, you could possibly even rig up an unmapped in-container area for tiny backup.
That should remove the question of whether there’s a mapping problem behind whatever’s going on.

Presumably you have the Destination as Local folder or drive, and GUI-navigated to the folder.
That would probably avoid the excess or wrong slashes that people sometimes type for destinations.

@Randy

verified that the container can see every directory.

I’m not a Docker expert, but isn’t it actually that the process of interest (whatever UID it is) can see it?
There are still permissions that vary inside a container. About → System info shows what Duplicati is.