Failed to start Syncthing/SyncTrayzor

I’ve been unable to start Syncthing (SyncTrazor ver 2.1) for a few weeks and the logs give me this error “2026-07-22 08:43:39 ERR Failed to initialize config (error=“config file version (52) is newer than supported version (51); if this is expected, use --allow-newer-config to override” log.pkg=main)”

I don’t recall upgrading anything, so I’ve no idea why this is happening. I know it gives an explanation and a solution, but I don’t know how to implement it.

Any help would be appreciated please. Thanks.

The error means that your syncthing version was unexpectedly downgraded. Something must have changed on your system for this to happen.

This used to be a common problem for SyncTrayzor v1. It happened when you uninstall and then re-install SyncTrayzor again. SyncTrayzor v2 has multiple safeguards in place which should prevent this problem, but certain unknown edge cases apparently still trigger this.

To fix this, you should upgrade syncthing to the latest version again. Download the latest base syncthing (https://github.com/syncthing/syncthing/releases/download/v2.1.2/syncthing-windows-amd64-v2.1.2.zip), unpack the zip and move syncthing.exe to %AppData%\SyncTrayzor\syncthing.exe. Then launch SyncTrayzor as usual.

Amazing! That worked like a charm. Thank you for the very speedy solution.