Getting an error at the end of a backup

Support
1

I have just started using Dupicati and have two backup tasks scheduled.

I am receiving the following warning. I think this is quite some time after the backup has completed.

Duplicati.Library.Main.Operation.Backup.FileBlockProcessor.FileEntry-PathProcessingFailed]: Failed to process path: C:\Users\john\AppData\Roaming\Thunderbird\Profiles\pbznxji7.default-release\parent.lock

Running Duplicati - 2.0.6.1_beta_2021-05-03
The task was scheduled to run at 17:00 but I did not look at the computer until about 1720 or so. Nothing appeared to have happened and then the error message appeared.

2

I get that too. It appears to be a file “locked” by Thunderbird, thus preventing Duplicati from accessing it. If you close Thunderbird before running the backup, Duplicati should be able to grab it.
Since the file is always empty (0 bytes), I have chosen to exclude it from the backup by adding a “Exclude file” filter in Duplicati.

3

I would have expected Duplicati to be able to backup opened files via the Volume Shadow Service.

I have done as you suggested and eliminated that file from the backup and it seems to have solved the problem but I would appreciate an explanation as to why it is necessary. I am still evaluating Duplcati as my backup solution.

4

It can as long as configure the –snapshot-policy option and run Duplicati elevated.

5

Duplicati as a service - more complicate than it need be is the start, and there is much more there.
Of course, one can run as a Windows service as SYSTEM, but it may be overkill – and takes setup.

The rest of this assumes a more usual installation, and a more ordinary user account via Settings.

VSS requires Administrators group privileges, and you don’t have that even on an account labelled
Administrator in Settings until you manually approve a Windows User Account Control prompt.

User Account Control and Administrator Rights on Windows 10 has a nice writeup. Here’s a demo:

Windows Settings "Accounts" lets you choose "Standard User" or "Administrator".
The first account created at Windows install is labelled as an "Administrator".
This label is potential, not initially in effect. The UAC prompt enables power.
Here's a demo in account where "Settings" shows "Administrator" "account type":

It is, however, not fully in the "Administrators" group until UAC prompt accept.
Until then, it is relatively safe, but also lacks power, e.g. to administer VSS.

After signing into the account, but before going through "Run as administrator":

C:\>whoami /groups

GROUP INFORMATION
-----------------

Group Name                                                    Type             SID          Attributes
============================================================= ================ ============ ==================================================
Everyone                                                      Well-known group S-1-1-0      Mandatory group, Enabled by default, Enabled group
NT AUTHORITY\Local account and member of Administrators group Well-known group S-1-5-114    Group used for deny only

Using "Run as administrator" and manual confirm at UAC prompt:

C:\>whoami /groups

GROUP INFORMATION
-----------------

Group Name                                                    Type             SID          Attributes
============================================================= ================ ============ ===============================================================
Everyone                                                      Well-known group S-1-1-0      Mandatory group, Enabled by default, Enabled group
NT AUTHORITY\Local account and member of Administrators group Well-known group S-1-5-114    Mandatory group, Enabled by default, Enabled group