KB: Resolving 500 The Service is Unavailable Error for SVN Projects
Created: January 21, 2026 | Updated: January 21, 2026
Altium On-Prem Enterprise Server
After upgrading the Altium On-Prem Enterprise Server, users may encounter a "500: The service is unavailable" error when opening projects stored in SVN repositories. This issue is typically caused by disabled SVN support in the server configuration or an outdated license. To resolve it, SVN mode must be re-enabled in the configuration file, the server license refreshed, and IIS or the server restarted to apply changes. This article outlines the causes and provides step-by-step instructions to restore access to SVN-based projects.
Solution Details
SVN Projects Fail to Open After Server Upgrade
PLEASE NOTE : this issue occurs in 7.1 and below where SVN is available in those versions.
Why SVN Projects Fail After Upgrade
- SVN repository support is inadvertently disabled during the upgrade.
- The server configuration file (
LocalVault.ini) is set to disable SVN. - The Enterprise Server license has not been refreshed post-upgrade.
- IIS or server services have not been restarted to apply configuration changes.
What to Do
To resolve this issue, follow one or more of the steps below:
- Enable SVN mode in the configuration file
- Refresh the Enterprise Server license
- Restart IIS or the server
- Reconnect the client to the server
How to Do It
- Enable SVN Mode
- Open the
LocalVault.iniconfiguration file. - Locate the line:
SvnMode=None - Change it to:
SvnMode=Full - Save the file.
- Open the
- Apply Configuration Changes
- Open an elevated Command Prompt.
- Run the command:
IISreset /Restart - If this does not resolve the issue, restart the server manually.
- Refresh Enterprise Server License
- Ensure the server license is refreshed after the upgrade to retain SVN support.
- Refer to the licensing section in the documentation: KB: Safeguard Against Unexpected Errors During On-Premise Server Upgrade
- Local Version Control Service
- KB: SVN Discontinuation with AES 7.2.1