Backup fails - Fatal error

Hi guys,

unfortunately I cannot complete my backup anymore.
After about 20 minutes I get this error message:

{“ClassName”:“System.IO.IOException”,“Message”:“Der Netzwerkpfad wurde nicht gefunden.\r\n”,“Data”:null,“InnerException”:null,“HelpURL”:null,“StackTraceString”:" bei System.IO.__Error.WinIOError(Int32 errorCode, String maybeFullPath)\r\n bei System.IO.DriveInfo.get_TotalSize()\r\n bei Duplicati.Library.Backend.File.get_Quota()\r\n bei Duplicati.Library.Main.Operation.FilelistProcessor.RemoteListAnalysis(BackendManager backend, Options options, LocalDatabase database, IBackendWriter log, String protectedfile)\r\n bei Duplicati.Library.Main.Operation.FilelistProcessor.VerifyRemoteList(BackendManager backend, Options options, LocalDatabase database, IBackendWriter log, String protectedfile)\r\n bei Duplicati.Library.Main.Operation.BackupHandler.PreBackupVerify(BackendManager backend, String protectedfile)\r\n bei Duplicati.Library.Main.Operation.BackupHandler.d__19.MoveNext()\r\n— Ende der Stapelüberwachung vom vorhergehenden Ort, an dem die Ausnahme ausgelöst wurde —\r\n bei System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()\r\n bei CoCoL.ChannelExtensions.WaitForTaskOrThrow(Task task)\r\n bei Duplicati.Library.Main.Controller.<>c__DisplayClass13_0.b__0(BackupResults result)\r\n bei Duplicati.Library.Main.Controller.RunAction[T](T result, String& paths, IFilter& filter, Action`1 method)\r\n bei Duplicati.Library.Main.Controller.Backup(String inputsources, IFilter filter)\r\n bei Duplicati.Server.Runner.Run(IRunnerData data, Boolean fromQueue)",“RemoteStackTraceString”:null,“RemoteStackIndex”:0,“ExceptionMethod”:“8\nWinIOError\nmscorlib, Version=, Culture=neutral, PublicKeyToken=b77a5c561934e089\nSystem.IO.__Error\nVoid WinIOError(Int32, System.String)”,“HResult”:-2147024843,“Source”:“mscorlib”,“WatsonBuckets”:null}

I’m making a backup on a webdav connected drive.
I am able to access the drive via Windows Explorer…

I have no Idea what to do now… Could you please help me what to do next?
Thank you!

Update: I’m having some packet loss at my incoming internet connection… could be a reason…

Google Translate thinks “Der Netzwerkpfad wurde nicht gefunden” is “The network path was not found” so that sounds like a reasonable connection. Unfortunately it may also be within Windows (see below).

Is your connection through Windows WebDAV like as described in Accessing WebDAV with Windows?

WebDAV is also supported directly by Duplicati, and (unlike Local folder or drive) it won’t check quotas, which may be a bad thing (if you like quotas), or good thing (because checking looks like it was failing).

Regardless, Duplicati can’t do network backups until networking works. Your failure in PreBackupVerify possibly would have instead been a failure later on in the backup, if File.get_Quota() hadn’t hit first.

This reminds me of an issue I had recently with fatally high OneDrive packet losses, while B2 held fine. Losses visible with mtr (a traceroute program) in Linux. Several days later, Internet got healthy again… Watching Wireshark show TCP doing its best (but not succeeding) to get data moved was another clue.