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