Error After Upgrade to 13.1. Failed to connect to the Veeam Updater Service

Certificate did nothing.

On August 27:

• The settings synchronization started at approximately 9:09:20 PM.
• It failed at 9:09:21 PM.
• The Veeam Updater Service did not enter the running state until 9:09:58 PM.

On August 29:

• The settings synchronization started at approximately 9:46:11 AM.
• It failed at 9:46:12 AM.
• The Veeam Updater Service did not enter the running state until 9:46:46 AM.

In both failures, Veeam Backup & Replication attempted to log in to the updater before the updater had fully started. The stack trace shows the failure occurring in VeeamUpdaterClient.Login() and VeeamUpdaterClient.Connect().

You should work with support to get this addressed then.

No support is FULLY aware of this issue.  They just need to get it fixed.  Please stop with just random posting, this issue is real, doesn’t seem to affect backups which is good, but people need to post their issues and solutions.

That is good and I DO NOT post randomly so please check my account if needed.  I get posting which is great for community collaboration but in the end some issues have to be fixed by support then most post the solution here.

You’re a poster and we appreciate your blurb to contact support.

Product:
Veeam Backup & Replication Community Edition for Windows

Installed versions:
Veeam Backup & Replication: 13.1.1.18
Veeam Backup Service executable: 13.1.0.411
Veeam Backup Manager executable: 13.1.0.411
Veeam Updater: 13.1.202.0
Veeam Updater Plug-in for VBR: 13.1.1.18

Reported email error:
Failed to synchronize update settings.
Error: Failed to connect to the Veeam Updater service.

Detailed log error:
The HTTP status code of the response was not expected (503).
Status: 503

Failure component:
Veeam.Updater.Rest.Client.AutoGenerated.v3_1.Client_v3_1.LoginAsync
Veeam.Backup.UpdaterClient.VeeamUpdaterClient.Login
Veeam.Backup.UpdaterClient.VeeamUpdaterClient.Connect
Veeam.Backup.Core.CVeeamUpdaterSettingsSyncTask.Perform

Synchronization history:
August 28, 2026 2:28:14 PM - Success
August 28, 2026 2:28:23 PM - Success
August 28, 2026 4:37:40 PM - Failed
August 28, 2026 5:12:33 PM - Failed
August 29, 2026 6:45:46 AM - Failed
August 30, 2026 6:45:52 AM - Success

Observed service timing during the August 29 failure:
6:45:41 AM - Veeam Backup Update Service entered Running
6:45:46 AM - Veeam Updater Package Manager Service entered Running
6:45:46 AM - Update Settings Synchronization failed with HTTP 503
6:46:10 AM - Veeam Updater Service entered Running

Current service status:
Veeam Backup Service - Running
Veeam Backup Update Service - Running
Veeam Updater Package Manager Service - Running
Veeam Updater Service - Running
Veeam Backup Server RESTful API Service - Running
Veeam Web Service - Running

Current local updater endpoints:
127.0.0.1:13136 - Veeam.Updater
127.0.0.1:13137 - Veeam.Updater.PackageManager

Additional observations:
The server has generated Software Update Summary emails reporting the synchronization failure on two consecutive days.

The August 29 failed session reached the local updater endpoint but received HTTP 503 during the updater login request. The Veeam Updater Service did not enter the Running state until approximately 24 seconds after the failed synchronization.

A subsequent synchronization on August 30 succeeded. During that successful session:
- The Veeam certificate was located.
- Remote certificate validation succeeded.
- SetVbrPluginProductInfo succeeded.
- SetSettings succeeded.
- The session completed with Success.

Request:
Please confirm whether this is a known Veeam 13.1.1.18 Windows updater startup/readiness issue. Please provide the applicable hotfix, retry configuration, or supported remediation. Please also confirm whether the version difference between the 13.1.1.18 installed product and the 13.1.0.411 Backup Service and Manager executables is expected.

As of this morning both systems passed. So maybe the certificate was the issue?  Give it a try for the initial error in this post.  Good luck and thankfully Veeam is a solid solution!

For our second issue of our VBR server job failing, we resolved the issue by disabling application-aware processing on the job as we do not require it. 

They had additional steps to delete the VeeamVssSupport service and rename C:\Windows\VeeamVssSupport folder to add _old. A new job with application-aware processing enabled would then recreate the folder.

We did not do those steps as the service and folder did not exist for us, and simply disabling application-aware processing had already stopped the errors. 

Glad to hear you were able to get the second issue resolved and it was simple.  Thanks for sharing the solution.