The Update installation cannot be performed because it requires the LocalSystem password to continue and it does not provide an option to change an existing account in the installation Wizard.
Veeam ONE Monitor Server service is running under the LocalSystem account which cannot be changed during the Update installation process.
In order to solve the issue, amend the Veeam ONE Monitor and Veeam ONE Reporter service credentials:
1. Open Services snap-in on the Veeam ONE server;
2. Find the Veeam ONE Monitor Server service and open the properties;
3. Navigate to the Log On tab;
4. Select This account option and specify your credentials using the Domain\Username prefix;
NOTE: The service account must have Local Administrator permissions.
5. Restart the service to apply the changes;
6. Perform the same steps for Veeam ONE Reporter Server service;
7. Install the Update.