Problem description
The Druva Enterprise Workloads agent installation or upgrade fails and rolls back during the final phase of the setup process. While older agent versions may install without issues, newer releases fail to complete, preventing the agent from being upgraded or reinstalled.
This issue typically reproduces in the following scenarios:
A previous installation or uninstallation of the Druva agent was interrupted or terminated abruptly.
The agent binaries or folders were deleted manually without using the official Windows Add/Remove Programs wizard.
An upgrade or reinstall is attempted on a host retaining orphaned registry keys from a previous version.
Cause
The installation fails because an orphaned Windows Event Log registry key or Windows Service entry from a prior installation still exists in the registry. During the final phase of setup, the installer attempts to register Druva-EnterpriseWorkloadsSVC under the Windows Application Event Log. Because the key already exists and overwrite permissions or handling are not permitted at this step, the installer encounters a collision, aborts the procedure, and rolls back all changes.
Traceback
The following entry appears in the installation log (EnterpriseWorkloads_Installer_<timestamp>.log or MSI log):
Failed to install Druva-EnterpriseWorkloadsSVC error: failed to install event log for the service: SYSTEM\CurrentControlSet\Services\EventLog\Application\Druva-EnterpriseWorkloadsSVC registry key already exists
Resolution
Execute the following steps on the affected Windows server using an account with local Administrator privileges.
Registry Backup Required
Exercise caution when modifying the Windows Registry. Incorrect modifications can cause severe operating system instability. Always create a registry backup or system restore point before proceeding.
Remove the stale Event Log registry entry Open an elevated PowerShell prompt (Run as Administrator) and run:
Remove-Item -Path "HKLM:\SYSTEM\CurrentControlSet\Services\EventLog\Application\Druva-EnterpriseWorkloadsSVC" -Recurse -Force
Check for an existing Druva service definition In the elevated prompt, verify if the service registration is still present:
sc.exe query Druva-EnterpriseWorkloadsSVC
Delete the orphaned service (if present) If step 2 reports
STATE: STOPPEDor lists the service properties, execute:sc.exe delete Druva-EnterpriseWorkloadsSVC
Clean up remaining service keys Verify and delete any leftover service key via PowerShell:
if (Test-Path "HKLM:\SYSTEM\CurrentControlSet\Services\Druva-EnterpriseWorkloadsSVC") { Remove-Item -Path "HKLM:\SYSTEM\CurrentControlSet\Services\Druva-EnterpriseWorkloadsSVC" -Recurse -Force }Reinstall the Druva Agent Restart the machine if prompted, then rerun the Druva Enterprise Workloads agent installer using Run as Administrator.
Verification
To verify that the fix is successful:
Ensure the installer finishes with "Installation Completed Successfully" without triggering a rollback.
Confirm the service starts and is running:
sc.exe query Druva-EnterpriseWorkloadsSVC
Expected output:
STATE : 4 RUNNING.Verify that the server successfully registers and shows connected in the Druva Management Console.